Layered product and capacitor

ABSTRACT

A layered product including a plurality of deposition units, each having a thin resin layer and a thin metal layer wherein the surface roughness of the thin resin layer is 0.1 μm or below, a protrusion forming component is not added to the thin resin layer or the surface roughness of the thin metal layer is 0.1 μm or below. The surface characteristics are improved regardless of the thickness of the layered product and the requirement of high performance thin film can be satisfied because the layered product contains no foreign matter. The layered product is suitably applicable to electronic parts, e.g., a capacitor, especially a chip capacitor.

This application is a divisional of application Ser. No. 09/554,582, nowU.S. Pat. No. 6,388,865 B1, which is a 371 of PCT/JP98/05155 filed Nov.16, 1998 filed May 16, 2000, which application(s) are incorporatedherein by reference.

TECHNICAL FIELD

A first aspect of the present inventions relates to a layered productformed by depositing a plurality of deposition units, each of whichincludes a resin thin film layer and a metal thin film layer.

A second aspect of the present inventions relates to a layered productincluding dielectric layers and metal thin films, in particular, alayered product suitably used for an electronic component such as acapacitor.

BACKGROUND ART

Regarding the First Invention

A layered product comprising resin thin film layers and metal thin filmlayers are used in a wide range of applications, for example, as amagnetic recording medium such as a magnetic tape, a wrapping materialor an electronic component.

The resin thin film layers used in such a layered product aremanufactured by melting and stretching a resin material into aself-supported film or by applying a solution of a resin materialdiluted with a solvent to a supporting base and drying the resin forcuring. However, the resin thin film layers obtained by the formermethod are provided with slight roughness on a surface of the film for asmall coefficient of friction by allowing a protrusion forming component(e.g., externally added particles) to be contained in the film in orderto provide the film with the conveyance properties. Moreover, the formermethod tends to require large scale equipment to manufacture the resinthin film layers. On the other hand, the resin thin film layers obtainedby the latter method may have large protrusions on the surfaces thereofcaused by defects generated in the coating film after drying. Moreover,some solvent may cause environmental problems. Furthermore, the smallestthickness of the resin thin film obtained by the above methods is only1μm, and neither of the above methods can produce thinner thin filmsstably.

To obtain thin resin layers stably, a method of forming a resin thinfilm on a supporting base in a vacuum has been proposed. In this method,a resin thin film is evaporated in a vacuum and adhered to a supportingbase to produce thin films. It is said that this method allows resinthin films to be formed with relatively small equipment that lessadversely affects the environment.

On the other hand, for formation of metal thin film layers, a method ofvacuum evaporation on a surface of a base that is moving at high speedis advantageous for mass production and is put in industrially practicaluse. The thickness of the metal thin film layer produced by this methodis very thin, so that the shape of the surface of the base is reflectedexactly on the surface of the metal thin film.

The recent needs for a layered product including resin thin film layersand metal thin films are directed to further degrees of compactness andhigh performance. Therefore, the tendency of forming thinner resin thinfilms and metal thin films and eliminating factors causing instabilitysuch as abnormal protrusions or foreign substances is increasinglystrengthened.

However, the layered product obtained by forming a metal thin filmlayer, for example by evaporation, on a resin thin film layer obtainedby melting and stretching a resin material, or applying a solution of aresin material diluted with a solvent to a supporting base and dryingfor curing have the following disadvantages. The resin thin films cannothave a small thickness, and may contain foreign substances or haveprotrusions inhibiting various characteristics on the surface thereof.Thus, a layered product that can satisfy the need for thinness and highperformance has not been obtained.

Furthermore, a layered product comprising metal thin film layers formed,for example by evaporation on resin thin film layers formed on asupporting base in a vacuum can have a small thickness. However, thesurface characteristics are not sufficient so that variouscharacteristics are not stable. Thus, this layered product cannotsatisfy the characteristics strictly required by the current need.

Regarding the Second Invention

The current need for compactness and high performance of electroniccomponents is increasingly strengthened, and this is the case forcapacitors as well. The capacitance of the capacitor is in proportion tothe area of the dielectric and in inverse proportion to the square ofthe thickness of the dielectric layer when the dielectric constant ofthe dielectric is the same. Therefore, in order to achieve a compactcapacitor and maintain or increase the capacitance thereof, it iseffective to make the dielectric layer thin and increase an effectivearea of a region where capacitance is generated.

One known example of a layered product comprising dielectric layers andmetal thin film layers used for electronic components such as capacitorsis a layered product for a film capacitor. This layered product isformed by layering or winding a metallized film obtained by depositing ametal thin film such as aluminum on a resin film such as polyester(e.g., PEN, PET), polyolefin (e.g., PP) or PPS by vacuum evaporation,sputtering or the like.

However, there is a limit for the thickness of the resin film due tovarious constraints such as handling properties or processability of thefilm during or after production. The thickness of currently used filmcapacitors can be as small as about 1.2 μm. Therefore, in order toincrease the capacitance of the capacitors further, it is necessary toincrease the effective area of the capacitance generation portion,namely, increase the number of times of layering or winding. However,this contradicts the requirement for compactness of the capacitor. Inother words, for film capacitors, the achievement of high levels of bothcompactness and large capacitance has reached the limit at the moment.

On the other hand, a layered product for a capacitor comprising adielectric layer and a metal thin film layer produced by a methodtotally different from that for the conventional film capacitor, whichallows the thickness of a dielectric layer to be about 1 μm, has beenproposed (U.S. Pat. No. 5,125,138). The layered product has the samelayered structure where dielectric resin layers and metal thin filmlayers are deposited sequentially as the conventional layered productfor layered type film capacitors. However, the layered product has about1000 depositions or more and has a thickness on the order of several mm.

However, the examination by the inventors of the present inventionrevealed that various problems arise in production of a capacitor withsuch a layered product in the same manner as with the conventionallayered product for layered type film capacitors.

For example, when thermal load or external pressure is applied to thelayered product in a pressurizing and heating press process duringproduction of the layered product or a process for mounting a capacitorformed of the layered product on a printed circuit board or the like,the layered product is damaged easily. Furthermore, in order to use thelayered product as a capacitor, it is necessary to form externalelectrodes on the sides of the layered product. Conventionally, for thelayered type film capacitors, the external electrodes are formed bymetal spraying. When this technique is applied to the above-describedlayered product, the adhesion strength between the metal thin films andthe external electrodes is poor so that failure of electrical connectionor falling of the external electrodes may occur.

It has turned out that these problems become more serious when thethickness of the dielectric layer is made even smaller to the extentthat cannot be achieved for the conventional film capacitor. Theseproblems cannot be avoided to achieve compactness and high capacitanceof a capacitor with the above-described layered product.

DISCLOSURE OF INVENTION

Regarding the First Invention

It is an object of the first invention to provide a layered productformed by depositing a plurality of deposition units each of whichincludes a resin thin film layer and a metal thin film layer that hasgood surface properties and contains no foreign substance, regardlessthe deposition thickness, and that therefore can satisfy the currentneed for a high performance thin film.

In order to achieve the above object, the first invention has thefollowing embodiments.

A layered product according to a first embodiment of the first presentinvention includes a plurality of deposition units, each of whichincludes a resin thin film layer and a metal thin film layer. Thesurface roughness of the resin thin film layer is not more than 0.1 μm.

A layered product according to a second embodiment of the first presentinvention includes a plurality of deposition units, each of whichincludes a resin thin film layer and a metal thin film layer. The resinthin film layer contains no protrusion forming component.

A layered product according to a third embodiment of the first presentinvention includes a plurality of deposition units, each of whichincludes a resin thin film layer and a metal thin film layer. Thesurface roughness of the metal thin film layer is not more than 0.1 μm.

The layered product according to the first present invention includes aplurality of deposition units, each of which includes a resin thin filmlayer and a metal thin film layer, and the surface roughness of theresin thin film layer is not more than 0.1 μm, the resin thin film layercontains no protrusion forming component, or the surface roughness ofthe metal thin film layer is not more than 0.1 μm. Therefore, thelayered product of the first present invention has good surfaceproperties and contains no foreign substance therein, regardless of thedeposition thickness. Thus, the requirement for a higher performancethin layered product can be met sufficiently.

Regarding the Second Invention

It is an object of the second invention to provide a layered productthat has strong resistance against thermal load and external pressureand has high adhesion strength with external electrodes formed thereonand that can achieve high levels of compactness and high capacitancewhen it is used as a capacitor, and to provide a capacitor using such alayered product.

In order to achieve the above object, the second invention has thefollowing embodiments.

A layered product according to a first embodiment of the second presentinvention includes an element layer, reinforcement layers deposited onboth sides of the element layer, and protective layers deposited furtheron both sides of the reinforcement layers. The element layer satisfies Aor B below, and the reinforcement layer satisfies C or D below:

A: A plurality of deposition units, each of which comprises a dielectriclayer, a first metal thin film layer and a second metal thin film layerthat are deposited on one surface of the dielectric layer and separatedby a belt-shaped electrically insulating portion, are deposited in sucha manner that the electrically insulating portions of adjacentdeposition units are deposited in different positions;

B: A plurality of deposition units, each of which comprises a dielectriclayer and a metal thin film layer that is deposited on one surface ofthe dielectric layer and in a portion except a belt-shaped electricallyinsulating portion on one end of the surface of the dielectric layer,are deposited in such a manner that the electrically insulating portionsof adjacent deposition units are positioned in opposite sides;

C: comprising a deposition unit that comprises a resin layer, a firstmetal layer and a second metal layer that are deposited on one surfaceof the resin layer and separated by a belt-shaped electricallyinsulating band; and

D: comprising a deposition unit that comprises a resin layer and a metallayer that is deposited on one surface of the resin layer and in aportion except a belt-shaped electrically insulating band on one end ofthe surface of the resin layer.

A layered product according to a second embodiment of the second presentinvention includes an element layer and reinforcement layers depositedon both sides of the element layer. The element layer satisfies A or Bbelow, the reinforcement layer satisfies C or D below, and further atleast one of E or F is satisfied:

A: A plurality of deposition units, each of which comprises a dielectriclayer, a first metal thin film layer and a second metal thin film layerthat are deposited on one surface of the dielectric layer and separatedby a belt-shaped electrically insulating portion, are deposited in sucha manner that the electrically insulating portions of adjacentdeposition units are deposited in different positions;

B: A plurality of deposition units, each of which comprises a dielectriclayer and a metal thin film layer that is deposited on one surface ofthe dielectric layer and in a portion except a belt-shaped electricallyinsulating portion on one end of the surface of the dielectric layer,are deposited in such a manner that the electrically insulating portionsof adjacent deposition units are positioned in opposite sides;

C: comprising a deposition unit that comprises a resin layer, a firstmetal layer and a second metal layer that are deposited on one surfaceof the resin layer and separated by a belt-shaped electricallyinsulating band;

D: comprising a deposition unit that comprises a resin layer and a metallayer that is deposited on one surface of the resin layer and in aportion except a belt-shaped electrically insulating band on one end ofthe surface of the resin layer;

E: The thickness of the dielectric layer is different from that of theresin layer; and

F: The thickness of the metal thin film layer is different from that ofthe metal layer.

Furthermore, a capacitor of the present invention is produced using anyone of the above-described layered products.

With such embodiments, the layered product of the second presentinvention has strong resistance against thermal load or externalpressure, and has high adhesion strength with external electrodes whenthey are formed therein. In the case where it is used as a capacitor,high levels of compactness and high capacitance can be achieved.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a cross-sectional view taken in the thickness direction(deposition direction) schematically illustrating an example of alayered product of the first invention.

FIG. 2 is a cross-sectional view taken in the arrow direction of lineI—I in FIG. 1.

FIG. 3 is a cross-sectional view taken in the thickness direction(deposition direction) schematically illustrating another example of alayered product of the first invention.

FIG. 4 is a cross-sectional view taken in the thickness direction(deposition direction) schematically illustrating yet another example ofa layered product of the first invention.

FIG. 5 is a cross-sectional view taken in the arrow direction of lineII—II in FIG. 4.

FIG. 6 is a cross-sectional view taken in the thickness direction(deposition direction) schematically illustrating still another exampleof a layered product of the first invention.

FIG. 7 is a cross-sectional view taken in the thickness direction(deposition direction) schematically illustrating an example of areinforcement layer deposited for the layered product of the firstinvention.

FIG. 8 is a cross-sectional view taken in the thickness direction(deposition direction) schematically illustrating another example of areinforcement layer deposited for the layered product of the firstinvention.

FIG. 9 is a cross-sectional view taken in the thickness direction(deposition direction) schematically illustrating yet another example ofa reinforcement layer deposited for the layered product of the firstinvention.

FIG. 10 is a cross-sectional view taken in the thickness direction(deposition direction) schematically illustrating still another exampleof a reinforcement layer deposited for the layered product of the firstinvention.

FIG. 11 is a schematic perspective view illustrating an example of achip capacitor using the layered product of the first invention.

FIG. 12 is a schematic view illustrating an example of a productionapparatus for producing the layered product of the first invention.

FIG. 13 is a schematic cross-sectional view illustrating the internalstructure of an apparatus for forming a resin thin film used in theproduction apparatus in FIG. 12.

FIG. 14 is a schematic view illustrating another example of a productionapparatus for producing the layered product of the first invention.

FIG. 15 is a schematic front view of an apparatus for applyingpatterning material used in the production apparatus in FIG. 12.

FIG. 16 is a schematic view illustrating a device for retracting theapparatus for applying patterning material and moving the applicationposition of the patterning material.

FIG. 17 is a partial perspective view illustrating an example of thestructure of a flat layered base element.

FIG. 18 is a partial perspective view illustrating another example ofthe structure of a flat layered base element.

FIG. 19 is a schematic view illustrating another example of a productionapparatus for producing the layered product of the first invention.

FIG. 20 is a perspective view illustrating the outline of the depositionstructure of a first layered product of the second invention.

FIG. 21 is a perspective view illustrating the outline of the depositionstructure of a second layered product of the second invention.

FIG. 22 is a cross-sectional view taken in the thickness direction(deposition direction) schematically illustrating an example of anelement layer having a structure A of the layered product of the secondinvention.

FIG. 23 is a cross-sectional view taken in the arrow direction of lineIII—III in FIG. 22.

FIG. 24 is a cross-sectional view taken in the thickness direction(deposition direction) schematically illustrating another example of anelement layer having a structure A of the layered product of the secondinvention.

FIG. 25 is a cross-sectional view taken in the thickness direction(deposition direction) schematically illustrating an example of anelement layer having a structure B of the layered product of the secondinvention.

FIG. 26 is a cross-sectional view taken in the arrow direction of lineVI—VI in FIG. 25.

FIG. 27 is a cross-sectional view taken in the thickness direction(deposition direction) schematically illustrating another example of anelement layer having a structure B of the layered product of the secondinvention.

FIG. 28 is a cross-sectional view taken in the thickness direction(deposition direction) schematically illustrating an example of areinforcement layer where a plurality of deposition units having thestructure C are deposited of the layered product of the secondinvention.

FIG. 29 is a cross-sectional view taken in the thickness direction(deposition direction) schematically illustrating another example of areinforcement layer where a plurality of deposition units having thestructure C are deposited of the layered product of the secondinvention.

FIG. 30 is a cross-sectional view taken in the thickness direction(deposition direction) schematically illustrating an example of areinforcement layer where a plurality of deposition units having thestructure D are deposited of the layered product of the secondinvention.

FIG. 31 is a cross-sectional view taken in the thickness direction(deposition direction) schematically illustrating another example of areinforcement layer where a plurality of deposition units having thestructure D are deposited of the layered product of the secondinvention.

FIG. 32 is a cross-sectional view taken in the thickness direction(deposition direction) schematically illustrating still another exampleof a reinforcement layer where a plurality of deposition units havingthe structure D are deposited of the layered product of the secondinvention.

FIG. 33 is a schematic perspective view of an example where externalelectrodes are formed in the first layered product (FIG. 20) of thesecond invention.

FIG. 34 is a schematic view illustrating an example of a productionapparatus for producing the layered product of the second invention.

FIG. 35 is a schematic perspective view of an apparatus for applyingpatterning material.

FIG. 36 is a schematic view illustrating a device for retracting theapparatus for applying patterning material and moving the applicationposition of the patterning material.

FIG. 37 is a partial perspective view illustrating an example of thestructure of a flat layered base element.

FIG. 38 is a partial perspective view illustrating another example ofthe structure of a flat layered base element.

BEST MODE FOR CARRYING OUT THE INVENTION

Regarding the First Invention

The layered product of the first invention is formed by depositing aplurality of deposition units, each of which includes a resin thin filmlayer and a metal thin film layer. The layered product formed bydepositing a plurality of deposition units is used in a wide range ofapplications such as magnetic recording materials, wrapping materials,electronic component materials or the like, and small depositionthickness and stability of the characteristics are significantlyrequired. In the deposition unit, a resin thin film layer and a metalthin film layer may be deposited successively, or another layer can beinterposed therebetween. Other layers can be deposited on and below orbetween the layered product(s) of the present invention.

The surface roughness of the resin thin film layer of the layeredproduct of the present invention is required to be 0.1 μm or less,preferably 0.04 μm or less, and most preferably 0.02 μm or less. Thesurface roughness of the metal thin film layer of the layered product ofthe present invention is required be 0.1 μm or less, preferably 0.04 μmor less, most preferably 0.02 μm or less. If the surface roughness islarger than these ranges, no improvement of characteristics of theresultant layered product can be achieved for various applications, andits characteristics become unstable. For example, when applied to amagnetic recording medium, high-density recording becomes difficult,large surface protrusions cause dropout, and the reliability of therecording decreases. When applied to electronic components, high-densityintegration becomes difficult, an electric field is concentrated onlarge surface protrusions, and the resin thin film may be leached or themetal thin film may be burnt.

Furthermore, the surface roughness of the resin thin film layer ispreferably {fraction (1/10)} or less, more preferably {fraction (1/25)}or less, and most preferably {fraction (1/50)} or less of the thicknessof the resin thin film layer. If the surface roughness of the resin thinfilm layer is too large relative to the thickness of the resin thin filmlayer, the concentration of an electric field or magnetic field and/orfailure of smoothing of adjacent metal thin film layers occur.Furthermore, the surface roughness of the metal thin film layer ispreferably {fraction (1/10)} or less, more preferably {fraction (1/25)}or less, and most preferably {fraction (1/50)} or less of the thicknessof the resin thin film layer or the thickness of the metal thin filmlayer. If the surface roughness of the metal thin film layer is toolarge relative to the thickness of the resin thin film layer or thethickness of the metal thin film layer, the concentration of an electricfield or magnetic field, failure of smoothing of adjacent resin thinfilm layers, and/or the concentration of current occur.

In this specification, surface roughness refers to the ten point averageroughness Ra, measured with a contact-type surface meter having adiamond needle of 10 μm tip diameter and a 10 mg measuring load. Tomeasure the surface roughness of a resin thin film layer, the needle iscontacted directly with the surface of the resin thin film layer, and tomeasure the surface roughness of a metal thin film layer, the needle iscontacted directly with the surface of the metal thin film layer. Themeasurement is required to be performed while eliminating the influenceof all other layered portions (for example, steps due to the presence ofthe electrically insulating portion and the electrically insulatingband, which will be described later).

The resin thin film layer of the layered product of the presentinvention should not include a protrusion forming component. Herein, aprotrusion forming component refers to a component that is added to amatrix resin or a component that is synthesized in a matrix resin andthat has an ability to form irregularities on the surface of the resinthin film layer. The protrusion forming component may be organic orinorganic. Examples thereof include inorganic particles, organicparticles, a resin incompatible to the matrix resin, and a byproductduring synthesis of a matrix polymer. The presence of such a componentprevents the intended characteristics from being obtained and causesinstability of the characteristics. For example, when applied to opticalrecording, the optical characteristics are unstable. When applied toelectronic components, the dielectric constant is varied. Furthermore,such a component forms various kinds of irregularities on the surfacesof the resin thin film layer and the metal thin film layer, so that thesurface roughness becomes large and the above-described problems arecaused.

There is no particular limitation regarding the thickness of the resinthin film layer, and the thickness can be determined suitably by the useto which the layered product is applied. However, the thickness ispreferably 1 μm or less, more preferably 0.7 μm or less, and mostpreferably 0.4 μm or less. A thinner resin thin film layer can fulfillthe requirement for compactness of the layered product. For example,when the layered product is used as a capacitor, as the thickness of theresin thin film layer that serves as the dielectric layer is smaller,the capacitance of the capacitor increases and the capacitor can becompact at the same time. Furthermore, since the layered product of thepresent invention has good surface characteristics even if the resinthin film layer is thin, the above-described problems are not caused.

There is no particular limitation regarding the thickness of the metalthin film layer, and the thickness can be determined suitably by the useto which the layered product is applied. However, the thickness ispreferably 100 nm or less, more preferably 50 nm or less, and mostpreferably 10-40 nm. Furthermore, the film resistance is preferably 2Ω/□or more, more preferably 3Ω/□ or more, and most preferably 3-10Ω/□. Whenthe metal thin film layer is thicker than the above ranges, or the filmresistance is smaller than the above ranges, the thickness of thelayered product is too large to achieve a compact product or thecharacteristics such as high frequency characteristics deteriorate. Whenthe metal thin film layer is thinner than the above ranges, or the filmresistance is larger than the above ranges, resistance against humiditydeteriorates or an allowable current value may be insufficient.

There is no particular limitation regarding the ratio of the thicknessof the resin thin film layer to the thickness of the metal thin filmlayer, and the ratio can be determined suitably by the use to which thelayered product is applied. However, when the layer is used as acapacitor, the ratio is preferably 20 or less, and more preferably 15 orless. When the ratio is in these ranges, in the case where a pin-hole inthe resin thin film layer serving as the dielectric layer causes theopposing metal thin film layer to be electrically short-circuited, themetal thin film layer is burnt or leached by overcurrent. Thus, aself-healing function of removing a defect is effected well.

The curing degree of the resin thin film layer is preferably 50-95%,more preferably 70-90% in terms of the handling properties and thestability of the characteristics of the layered product. The curingdegree means the extent of polymerization and/or crosslinking of theresin thin film layer. If the curing degree is smaller than theseranges, the following problems are caused. The layered product can bedeformed easily or the metal thin film layer is ruptured orshort-circuited, for example by an external pressure applied in apressing step during production of the layered product or in variousapplications of the layered product such as a process for mounting thelayered product as an electronic component in a circuit board. On theother hand, if the curing degree is larger than these ranges, problemssuch as cracking may arise in the case where a cylindrical continuouslayered product is removed from a can roller in the production processof the layered product which will be described later, in the case wherea flat layered base element is obtained by pressing, or in the casewhere an external pressure is applied in various applications of thelayered product. In the case where external electrodes are formed in thelayered product for an application as an electronic component (see FIG.11), sprayed metal particles hardly penetrate between the metal thinfilm layers during the formation of the external electrodes so that theadhesion strength of the external electrodes becomes weak. To determinethe curing degree of the present invention, the ratio of the absorbanceof the C═O groups and the C═C groups (1600 cm⁻¹) is determined with aninfrared spectrophotometer, the ratio of each monomer and the curedproduct is determined, and the curing degree is defined as 1 minus thereduced absorption ratio.

Possible materials for the metal thin film layer include aluminum,copper, zinc, nickel, their compounds, their oxides, and the oxides oftheir compounds. Of these, aluminum is preferable, because of itsadhesiveness and low cost. The metal thin film layer also can include atrace amount of other components in addition to these as the maincomponent.

In the present invention, a resin thin film material can be any materialas long as it can be deposited in a thickness of about 1 μm or less andthe required characteristics for various applications of the layeredproduct can be satisfied. For example, for the resin thin film layer ofthe layered product to be used as an electronic component, a materialcomprising an acrylate resin or a vinyl resin as a main component ispreferable. More specifically, a polymer of polyfunctional(meth)acrylate monomer or polyfunctional vinyl ether monomer ispreferable. In particular, a polymer of dicyclopentadiene dimethanoldiacrylate, cyclohexane dimethanol divinyl ether monomer or a polymer ofmonomer with substituted hydrocarbon groups is preferable because oftheir electrical properties.

The layered product of the present invention includes a resin thin filmlayer and a metal thin film layer. The metal thin film layer depositedon the resin thin film is not necessarily continuous but may be dividedinto several portions. FIG. 1 is a cross-sectional view taken in thethickness direction illustrating an example of such a layered product.FIG. 2 is a cross-sectional view taken in the arrow direction of lineI—I in FIG. 1. The metal thin film layer deposited on a resin thin filmlayer 11 is divided by a belt-shaped electrically insulating portion 13into a first metal thin film layer 12 and a second metal thin film layer14. The number of the electrically insulating portions on the resin thinfilm layer is not limited to one and may be plural, and the metal thinfilm layer can be divided into three or more. Thus, when the metal thinfilm layer is divided into a plurality of portions, for example, eachmetal thin film layer can be used as an electrode having a differentelectric potential from each other when the layered product is appliedto an electronic component.

For example, as shown in FIG. 1, the electrically insulating portion onthe resin thin film layer is single, and the electrically insulatingportion divides the metal thin film layer into two and is positioned sothat the electrically insulating portions of adjacent deposition unitsare deposited in different positions. In other words, as shown in FIG.1, in the case where a deposition unit 15 of a layered product 10 isdeposited adjacent to a deposition unit 15 a, the electricallyinsulating portion 13 of the deposition unit 15 is provided in adifferent deposition position from that of an electrically insulatingportion 13 a of the deposition unit 15 a. Thus, the deposition unitshaving the electrically insulating portions deposited in differentpositions are deposited sequentially. In this case, a capacitor can beformed by forming external electrodes on the side portions of thelayered product (see FIG. 11). In other words, an external electrode(not shown) for connecting the first metal thin film layer 12 of thedeposition unit 15 and the first metal thin film layer 12 a of thedeposition unit 15 a adjacent thereto in substantially the same electricpotential is provided, and an external electrode (not shown) forconnecting the second metal thin film layer 14 of the deposition unit 15and the second metal thin film layer 14 a of the deposition unit 15 a insubstantially the same electric potential is provided, and an electricalpotential difference is provided between the external electrodes. Inthis case, when the electrically insulating portions 13 and 13 a of thedeposition unit 15 and the deposition unit 15 a adjacent thereto areprovided in different positions, a capacitor having the followingelectrodes and dielectric (a portion where capacitance is generated) isformed: The first metal thin film layer 12 of the deposition unit 15 andthe second metal thin film layer 14 a of the deposition unit 15 a serveas the electrodes. A portion of the resin thin film layer 11 a that issandwiched by the first metal thin film layer 12 and the second metalthin film layer 14 a serves as the dielectric. Therefore, the phrase“the electrically insulating portions of the adjacent deposition unitsare provided in different deposition positions” means that thedeposition positions are different to the extent that the capacitancegeneration portion of a capacitor can be formed, as described above. Insuch a view, it is preferable to provide the electrically insulatingportions so that the area of the capacitance generation portion becomesas large as possible.

Portions other than the portion of the resin thin film layer 11 a thatis sandwiched by the first metal thin film layer 12 and the second metalthin film layer 14 a make no contribution to the formation of thecapacitance of the capacitor. At the same time, the second metal thinfilm layer 14 of the deposition unit 15 and the first metal thin filmlayer 12 a of the deposition unit 15 a do not function as electrodes ofthe capacitor. However, the second metal thin film layer 14 of thedeposition unit 15 and the first metal thin film layer 12 a of thedeposition unit 15 a are significant in that they improve the adhesionstrength of the external electrodes. In other words, the adhesionstrength with the external electrodes depends significantly on theconnection strength with the metal thin film layers and the connectionstrength with the resin thin film layers does not significantlycontribute to it. Therefore, even if the metal thin film layers do notcontribute to the capacitance generation for the capacitor, the presenceof these layers can improve the adhesion strength of the externalelectrodes when the capacitor is formed. The presence of such metal thinfilm layers is very significant especially in the case of a compactlayered product. The external electrodes are formed by metal spraying orthe like, and sprayed metal particles have a relatively large size. Whenthe resin thin film layer is extremely thin, the sprayed metal particleshardly penetrate between the metal thin film layers. Moreover, since thelayered product is small, an exposed metal thin film layer portion issmall. Therefore, it is significantly important to make a contact areawith the external electrodes as large as possible in order to ensure theadhesion strength of the external electrodes.

The electrically insulating portion has a belt-shape having a constantwidth W for ease of the production. The width W of the electricallyinsulating portion is not limited to a particular value, but preferablyabout 0.03-0.5 mm, more preferably about 0.05-0.4 mm, and mostpreferably about 0.1-0.3 mm when applied to a capacitor. If the width islarger than these ranges, the area of the capacitance generation portionas the capacitor becomes small, so that high capacitance is notrealized. On the other hand, when the width is smaller than theseranges, the electrical insulation cannot be obtained, or theelectrically insulating portion having a narrow width cannot be producedprecisely.

It is preferable that the deposition positions of the electricallyinsulating portions are not the same position over the layered product.As shown in FIG. 1, in the case where the electrically insulatingportions of the adjacent deposition units are provided in differentpositions and the electrically insulating portions of every otherdeposition unit are provided substantially in the same position, it ispreferable that the electrically insulating portions of every otherdeposition unit are not provided in the same position over the layeredproduct. FIG. 3 is a cross-sectional view taken in the thicknessdirection (deposition direction) schematically illustrating an exampleof an element layer 20 having such a structure. A deposition unit 25comprises a first metal thin film layer 22, a second metal thin filmlayer 24, an electrically insulating portion 23 and a resin layer 21. Asecond deposition unit 25 a comprises a first metal thin film layer 22a, a second metal thin film layer 24 a, an electrically insulatingportion 23 a and a resin layer 21 a. A third deposition unit 25 bcomprises a first metal thin film layer 22 b, a second metal thin filmlayer 24 b, an electrically insulating portion 23 b and a resin layer 21b. More specifically, with respect to the electrically insulatingportion 23 of the deposition unit 25, the position of the electricallyinsulating portion 23 b of the deposition unit 25 b, which is one unitapart from the deposition unit 25, is not the same position as that ofthe electrically insulating portion 23, but is displaced by a distance din the width direction of the electrically insulating portion. Thus, inthe same manner, the position of the electrically insulating portion ofthe deposition unit that is one unit further apart is displaced by d ineither one of the directions in the width direction of the electricallyinsulating portion. Alternatively, the position of the electricallyinsulating portion of the deposition unit one unit apart is in the sameposition, and the position of the electrically insulating portion of thedeposition unit three units apart can be displaced in the widthdirection of the electrically insulating portion.

Such displacement of the position of deposition of the electricallyinsulating portion can suppress roughness of the upper and lowersurfaces of the layered product. In other words, since there is no metalthin film layers in the electrically insulating portion, the thicknessof the deposition of this portion is smaller relative to the overalllayered product so that a recess is generated in portions 26 a and 26 bon the upper surface of the layered product. This recess may deterioratethe handling properties when mounting the layered product onto a printedcircuit board with a solder. In addition, when such a recess isgenerated, the larger the depth of the recess is, the more difficult itis to apply a patterning material onto the bottom of the recess asdescribed later in the production process of the layered product.Therefore, it is difficult to form a good electrically insulatingportion having a constant width. Moreover, the generation of the recesscauses inclination of the resin thin film layer and the metal thin filmlayer deposited on the recess at both sides of the electricallyinsulating layer, so that the thickness of the deposition of the resinthin film layer and the metal thin film layer becomes small locally.When the thickness of the deposition of the resin thin film layerbecomes small locally, the following problem arises. In the case wherethe layered product is used as a capacitor, the presence of that portionreduces the withstand voltage of the capacitor and causes ashort-circuit due to a pin-hole in the resin thin film layer. Moreover,when the thickness of the deposition of the metal thin film layerbecomes small locally, poor conductivity is likely to occur in thatportion.

Furthermore, the metal thin film layer of the present invention is notnecessarily deposited on the entire surface of the resin thin filmlayer, and can be deposited on a part thereof. FIG. 4 is across-sectional view taken in the thickness direction (depositiondirection) schematically illustrating an example of such a layeredproduct 30. FIG. 5 is a cross-sectional view taken along line II—II inFIG. 4 viewed from the arrow direction. A metal thin film layer 32deposited on a resin thin film layer 31 is deposited in a portion otherthan a belt-shaped electrically insulating portion 33, which is providedon one end of the resin thin film layer 31. In this manner, the metalthin film layer is not deposited on the entire surface of the resin thinfilm layer, but the electrically insulating portion is formed on one endof the resin thin film layer. Thus, the metal thin film layer of adifferent deposition unit can be used as an electrode having a differentelectrical potential, for example in an application to an electroniccomponent.

For example, deposition is performed in such a manner that theelectrically insulating portions of adjacent deposition units arelocated on the opposite sides. In other words, as shown in FIG. 4, inthe case where a deposition unit 34 is deposited adjacent to adeposition unit 34 a, deposition is performed in such a manner that whenan electrically insulating portion 33 of the deposition unit 34 isprovided on the right end of the resin thin film layer 31, anelectrically insulating portion 33 a of the deposition unit 34 a isprovided on the left end of a resin thin film layer 31 a. In thismanner, the deposition units are deposited sequentially in such a mannerthat the positions of the electrically insulating portions are locatedon the opposite sides. Thus, when external electrodes are formed on theside portions of the layered product (see FIG. 11), a capacitor can beformed. In other words, one external electrode is connected to the metalthin film layer 32 of the deposition unit 34, and the other externalelectrode is connected to the metal thin film layer 32 a of the adjacentdeposition unit 34 a, and an electrical potential difference is providedbetween the opposite external electrodes. The thus formed capacitor hasthe metal thin film layer 32 of the deposition unit 34 and the metalthin film layer 32 a of the deposition unit 34 a as the electrodes and aportion sandwiched between the metal thin film layer 32 and the metalthin film layer 32 a as the dielectric (capacitance generation portion).From such a viewpoint, it is preferable that the width of theelectrically insulating portion is as small as possible so that the areaof the capacitance generation portion is as large as possible.

The shape of the electrically insulating portion is a belt-shape havinga constant width W for ease of the production. The width W of theelectrically insulating portion is not limited to a particular value,but preferably about 0.03 to 0.5 mm, more preferably about 0.05 to 0.4mm, and most preferably about 0.1 to 0.3 mm to allow high capacitance ofthe capacitor, to make sure electrical insulation and to facilitate theproduction.

Furthermore, it is preferable that the widths of the electricallyinsulating portions deposited substantially in the same position are notthe same over the layered product. For example, as shown in FIG. 4, inthe case where the electrically insulating portions of adjacentdeposition units are deposited on the opposite sides, all the widths ofthe belt-shaped electrically insulating portions of every otherdeposition unit are not the same over the layered product. FIG. 6 is across-sectional view taken in the thickness direction (depositiondirection) schematically illustrating an example of a layered product 40having such a structure. A deposition unit 44 comprises a first metalthin film layer 42 and a resin layer 41. A second deposition unit 44 acomprises a first metal thin film layer 42 a, an electrically insulatingportion 43 a and a resin layer 41 a. A third deposition unit 44 bcomprises a first metal thin film layer 42 b and a resin layer 41 b.More specifically, as shown in FIG. 6, with respect to an electricallyinsulating portion 43 of the deposition unit 44, the width of anelectrically insulating portion 43 b of the deposition unit 44 b, whichis one unit apart from the deposition unit 44, is different from that ofthe electrically insulating portion 43. Thus, in the same manner, thewidth of the electrically insulating portion of the deposition unit thatis one unit apart is changed sequentially. Alternatively, the width ofthe electrically insulating portion is the same as that of theelectrically insulating portion of the deposition unit that is one unitapart, and the width of the electrically insulating portion of thedeposition unit three units apart can be changed.

When all the widths of the electrically insulating portions that aredeposited substantially in the same position are the same, the endportion where the electrically insulating portions are provided has asmall number of metal thin film layers. Therefore, the thickness of thedeposition in this portion is smaller relative to the overall layeredproduct so that a significant recess is generated on the upper surfaceof the layered product. This recess may deteriorate the handlingproperties when mounting the layered product onto a printed circuitboard with a solder. In addition, when such a recess is generated, thelarger the depth of the recess is, the more difficult it is to apply apatterning material onto the bottom of the recess as described later inthe production process of the layered product. Therefore, it isdifficult to form a good electrically insulating portion having aconstant width. Moreover, the generation of the recess causesinclination of the resin thin film layer and the metal thin film layerdeposited on the recess at a side of the electrically insulating layer,so that the thickness of the deposition of the resin thin film layer andthe metal thin film layer becomes small locally. When the thickness ofthe deposition of the resin thin film layer becomes small locally, thefollowing problem arises. In the case where the layered product is usedas a capacitor, the presence of that portion reduces the withstandvoltage of the capacitor and causes a short-circuit due to a pin-hole inthe dielectric film layer. Moreover, when the thickness of thedeposition of the metal thin film layer becomes small locally, poorconductivity is likely to occur in that portion.

In the above-described cases, it is preferable that the surfaceroughness of the resin thin film layer where the electrically insulatingportion is deposited is twice or less, more preferably equal to or lessthan the surface roughness of the resin thin film layer where the metalthin film layer is deposited. Unless the former and the latter satisfythis relationship, this results in the deposition where the layers aboveand below the electrically insulating portion have a large surfaceroughness, so that electric field concentrations or currentconcentrations occur, resulting in poor insulating properties of theelectrically insulating portion.

The number of depositions for deposition units, each of which includesthe resin thin film layer and the metal thin film layer, is not limitedto a particular number and can be determined suitably depending on theuse of the layered product. For example, in the case where the layeredproduct is used as a capacitor with a large capacitance, the number ofdepositions is preferably 1000 or more, more preferably 2000 or more,and most preferably 3000 or more. As the number of depositions islarger, the obtained capacitor can have larger capacitance when thelayered product is used as the capacitor. Furthermore, the layeredproduct of the present invention can have a high adhesion strength withthe external electrodes when a reinforcement layer and a protectivelayer as described layer are formed even if the resin thin film layer isthin. Moreover, the layered product of the present invention can havesufficient resistance against thermal load or external pressure. Inaddition, when the thickness of the resin thin film layer is small, theoverall thickness is not very large even if the number of depositions islarge. Therefore, if the volume is the same, the obtained capacitor canhave a larger capacitance than that of a conventional film capacitor. Ifthe capacitance is the same, the obtained capacitor can be smaller thana conventional film capacitor.

The layered product of the present invention can have a layered producthaving a different deposition form on at least one surface of theabove-described layered product or between the above-described layeredproducts depending on the use or required characteristics. For example,a reinforcement layer including a plurality of deposition units, each ofwhich includes a resin layer and a metal layer deposited on one surfaceof the resin layer can be deposited on at least one surface of theabove-described layered product.

Such a reinforcement layer is effective to prevent the above-describedlayered product portion from being damaged by thermal load or externalpressure in the process of manufacturing the layered product, or invarious applications of the layered product such as in the process ofmounting the layered product on a printed circuit board as an electroniccomponent. Moreover, the reinforcement layer, which has a metal thinfilm layer, is effective to increase the adhesion strength of theexternal electrodes (see FIG. 11). That is to say, the adhesion strengthof the external electrodes is mainly affected by the strength of theconnection with the metal layer, whereas the strength of the connectionwith the resin layer contributes only little to the adhesion strength.Consequently, by providing a reinforcement layer comprising a metal thinfilm layer, the adhesion strength of the external electrode can besignificantly increased when a capacitor is formed. In the case wherethe layered product is provided with external electrodes and is used asa capacitor, the reinforcement layer can function as a capacitancegeneration portion of the capacitor, but the capacitor design can besimplified when it does not function as such.

The reinforcement layer can be provided on only one surface or bothsurfaces of the layered product. However, it is preferable to providethe reinforcement layer on both sides, because protection of an elementlayer and the adhesion strength of the external electrodes improve moresignificantly.

The reinforcement layer can be deposited in contact with theabove-described layered product or can have another layer therebetween.

It is preferable to deposit a plurality of deposition units for thereinforcement layer in order to exert the above-described effects of thereinforcement layer more significantly.

The thickness (overall thickness on one surface) of the reinforcementlayer is preferably 20 μm or more, more preferably 50 to 500 μm, andmost preferably 100 to 300 μm to provide the effects sufficiently.

The deposition form of the reinforcement layer can be determinedsuitably, for example by the application of the layered product.However, when the layered product is used as a capacitor, anelectrically insulating band is formed on the resin layer. Without theelectrically insulating band, when the external electrodes are opposedon both sides of the layered product (see FIG. 11), the oppositeexternal electrodes would be short-circuited via the metal layer. Theshape of the electrically insulating band is a belt-shape having aconstant width for ease of the production or the like. It is sufficientto form one electrically insulating band for insulation of the oppositeexternal electrodes, but the number of the electrically insulating bandscan be two or more.

FIG. 7 is a cross-sectional view taken in the thickness direction(deposition direction) schematically illustrating an example of areinforcement layer having a structure where a plurality of depositionunits are deposited. In each of the deposition units, two metal layersthat are separated by a belt-shaped electrically insulator on a resinlayer are deposited on the resin layer.

A reinforcement layer 50 includes at least one deposition unit 55comprising a resin layer 51 and a first metal layer 52 and a secondmetal layer 53 that are deposited on one surface of the resin layer 51.The first metal layer 52 and the second metal layer 53 are separated byan electrically insulating band 54.

The position in which the electrically insulating band is provided isnot limited to a particular position, but it is preferable to provide itsubstantially in the central portion of the reinforcement layer, asshown in FIG. 7. When it is provided substantially in the same positionas the above-described electrically insulating portion, a large recessmay be generated on the upper surface of the layered product. Therefore,for example in mounting the layered product onto a printed circuit boardwith a solder, the handling properties are poor, or short-circuitfailure is more likely to occur due to poor soldering. In addition, whensuch a recess is generated, as the depth of the recess is larger, it ismore difficult to apply a patterning material to the bottom of therecess as described later. Therefore, it is difficult to form a goodelectrically insulating portion or electrically insulating band having aconstant width. Moreover, the generation of the recess causesinclination of the resin thin film layer and the metal thin film layerdeposited on the recess at both sides of the electrically insulatingportion, so that the thickness of the deposition becomes small.Therefore, a reduction of the withstand voltage as a capacitor, apin-hole in the dielectric layer and poor conductivity of the metal thinfilm layers are likely to occur.

When two or more deposition units as described above are deposited forthe reinforcement layer, it is preferable that the deposition positionsof the electrically insulating bands are not the same position over thereinforcement layer (the overall reinforcement layer on one side in thecase where the reinforcement layer is provided on both sides). Forexample, as shown in FIG. 8, in a reinforcement layer 60 the depositionposition of the electrically insulating band of the adjacent depositionunit is displaced by d1. Subsequently, the position of the electricallyinsulating band of the adjacent deposition unit is displaced by d1 ineither direction in the width direction of the electrically insulatingbands in the same manner. Alternatively, the positions of theelectrically insulating bands of two (or more) consecutive depositionunits can be the same position, and the position of the electricallyinsulating band of the third (or more) deposition unit can be displacedin the width direction of the electrically insulating band. When thedeposition positions are substantially the same position, a recess maybe generated in the electrically insulating portion on a surface of thelayered product. Therefore, the handling properties may be poor whenmounting the layered product onto a printed circuit board with a solder.In addition, when such a recess is generated, as the depth of the recessis larger, it is more difficult to apply a patterning material to thebottom of the recess as described later. Therefore, it is difficult toform a good electrically insulating band or electrically insulatingportion having a constant width. Moreover, the generation of the recesscauses inclination of the resin thin film layer and the metal thin filmlayer deposited on the recess at both sides of the electricallyinsulating portion, so that the thickness of the deposition becomessmall. Therefore, a reduction of the withstand voltage as a capacitor, apin-hole in the resin thin film layer and poor conductivity of the metalthin film layers are likely to occur.

On the other hand, when the displacement amount d1 is too large, notonly is the effect of eliminating the recess on the upper surface of thelayered product insignificant, but also the above-described problemsoccur due to the generation of the recess on the surface of the layeredproduct when the deposition position of the electrically insulating bandmatches the deposition position of the electrically insulating portion.Moreover, when the first metal layer and the second metal layer ofadjacent deposition units overlap, the overlapped portion forms acapacitor, which may cause a problem in the design of the capacitance orthe like.

FIG. 9 is a cross-sectional view taken in the thickness direction(deposition direction) schematically illustrating an example of areinforcement layer comprising a plurality of deposition units havinganother deposition form.

A reinforcement layer 70 of this example includes a plurality ofdeposition units 74, each of which comprises a resin layer 71 and ametal layer 72 deposited on one surface of the resin layer. A metallayer is not provided in a belt-shaped electrically insulating bandportion 73 on one end of a surface of the resin layer.

When two or more deposition units are deposited, it is preferable thatthe widths of the electrically insulating bands are not the same overthe reinforcement layer (the overall reinforcement layer on one side inthe case where the reinforcement layer is provided on both sides). Forexample, as shown in FIG. 10, with respect to an electrically insulatingband 81, the width of an electrically insulating band 82 of an adjacentdeposition unit is changed and further the width of an electricallyinsulating band 83 of an adjacent deposition unit is changed.Subsequently, the widths of the electrically insulating bands arechanged sequentially in the same manner. Alternatively, the widths ofthe electrically insulating bands of two (or more) consecutivedeposition units can be the same, and the width of the electricallyinsulating band of the third (or more) deposition unit can be changed.

When all the widths of the electrically insulating bands are the same,the number of deposited metal thin film layers is small in the endportion where the electrically insulating bands are formed so that thedeposition thickness in this portion is small relative to the overalllayered product. Thus, a significant recess may be generated on theupper surface of the layered product. This recess may deteriorate thehandling properties when mounting the layered product onto a printedcircuit board with a solder and may adversely affect the wettability ofthe solder. In addition, when such a recess is generated, as the depthof the recess is larger, it is more difficult to apply a patterningmaterial to the bottom of the recess as described later in theproduction process of the layered product. Therefore, it is difficult toform a good electrically insulating band or electrically insulatingportion having a constant width. Moreover, the generation of the recesscauses inclination of the resin thin film layer and the metal thin filmlayer deposited on the recess at a side of the electrically insulatingportion, so that the thickness of the deposition of the dielectric layerand the metal thin film layer becomes small locally. When the thicknessof the deposition of the resin thin film layer becomes small locally,the following problem arises. In the case where the layered product isused as a capacitor, the presence of that portion reduces the withstandvoltage of the capacitor and causes a short-circuit due to a pin-hole inthe resin thin film layer. Moreover, when the thickness of thedeposition of the metal thin film layer becomes small locally, poorconductivity is likely to occur in that portion.

The materials for the resin layer and the metal layer of thereinforcement layer are not limited to particular materials, and can bedetermined suitably depending on the application of the layered productand the required characteristics of the reinforcement layer. Forexample, the materials used for the dielectric layer and the metal thinfilm layer are preferable for the resin layer and the metal layer,respectively, in view of production efficiency. Furthermore, in somecases, materials different from those for the dielectric layer and themetal thin film layer are preferable for the purpose of adjusting theadhesion strength with external electrodes when they are formed oradjusting the curing degree or the mechanical strength of the overalllayered product or the like.

The curing degree of the resin layer of the reinforcement layer ispreferably 50-95%, more preferably 70-90%. If the curing degree issmaller than these ranges, the layered product can be deformed easily,for example by an external pressure applied in a pressing step duringproduction of the layered product or in various applications of thelayered product, for example in a process for mounting the layeredproduct as an electronic component in a printed circuit board. On theother hand, if the curing degree is larger than these ranges, problemssuch as cracking may arise in the case where a cylindrical continuouslayered product is removed from a can roller in the production processof the layered product, which is described later, in the case where aflat layered base element is obtained by pressing, or in the case wherean external pressure is applied in various applications of the layeredproduct, for example in a process for mounting the layered product as anelectronic component. Furthermore, when providing the layered productwith external electrodes, sprayed metal particles hardly penetratebetween the metal layers so that the adhesion strength of the externalelectrodes becomes weak.

The thickness of the resin layer T5 (FIG. 7) and T7 (FIG. 9) ispreferably 0.1 to 1 μm, and more preferably 0.1 to 0.6 μm. The thicknessof the metal layer T6 (FIG. 7) and T8 (FIG. 9) is preferably 100 to 500Å, and more preferably 200 to 400 Å. The film resistance is preferably 1to 10Ω/□, and more preferably 2 to 6Ω/□. In the case of FIG. 7, thethickness of the first metal layer can be different from that of thesecond metal layer, but the same thickness is preferable because auniform thickness of the overall layered product can be obtained.

The thicknesses T5 (FIG. 7) and T7 (FIG. 9) of the resin layer of thereinforcement layer are preferably larger than the thicknesses T1(FIG. 1) and T3 (FIG. 4) of the resin thin film layer. Furthermore, thethicknesses T6 (FIG. 7) and T8 (FIG. 9) of the metal layer of thereinforcement layer is preferably larger than the thicknesses T2(FIG. 1) and T4 (FIG. 4) of the metal thin film layer of the elementlayer. This is effective for protection of the layered product portioncomprising the resin thin film layer and the metal thin film layer andimprovement of the adhesion strength of the external electrodes. Inother words, a thicker resin layer or metal layer of the reinforcementlayer exerts a buffer function against external pressure or thermalstress more effectively. In addition, the external electrodes are formedby spraying or the like, and the particles of sprayed metal arerelatively rough and hardly penetrate between the metal thin film layerssufficiently. However, the thickness of the resin thin film cannot bemade large to ensure the capacitance for a capacitor. Therefore, thepenetration of the sprayed metal is facilitated by making the thicknessof the resin layer of the reinforcement layer thick, and thus theadhesion strength of the external electrodes can be improved with ease.Furthermore, the larger the area of the metal layer exposed to the sideis, the larger the contact area with the external electrodes is.Therefore, the adhesion strength of the external electrodes can beimproved by making the thickness of the metal layer of the reinforcementlayer thick.

A protective layer can be formed on at least one surface of the layeredproduct of the present invention.

The protective layer is effective to prevent the layered product portionfrom being damaged by thermal load or external pressure in the processof manufacturing the layered product, or in various applications of thelayered product such as in the process of mounting the layered producton a printed circuit board as an electronic component. Furthermore, withrespect to the improvement of the adhesion strength of the externalelectrodes, the protective layer has a certain effect, although thelevel of contribution thereof is lower than that of the metal thin filmlayers and the metal layers.

The protective layer can be provided on only one surface of the layeredproduct to exert its effect. However, it is preferable to provide theprotective layer on both surfaces to achieve the protection of thelayered product portion sufficiently. In this case, the protective layercan be provided via the reinforcement layer or without the reinforcementlayer. Furthermore, the protective layer can be deposited in contactwith the layered product or the reinforcement layer or can have anotherlayer therebetween.

The thickness of the protective layer is not limited to a particularvalue and can be determined suitably depending on the environment towhich the layered product is exposed. However, in order to provide theabove-described effect sufficiently, the thickness is preferably 2 μm ormore, more preferably 2 to 100 μm, and most preferably 4 to 30 μm.

The material for the protective layer is not limited to a particularmaterial, but when the material used for the resin thin film layerand/or the resin layer is used, the production efficiency can beimproved. On the other hand, a material different from that used for theresin thin film layer and/or the resin layer can be used to provide aspecific function for the protective layer. For example, epoxy estersuch as 2-hydroxy-3-phenoxypropyl acrylate is preferable for betteradhesion between the protective layer and the reinforcement layer.

The curing degree of the protective layer is preferably 50-95%, morepreferably 70-90%. If the curing degree is smaller than these ranges,the layered product can be deformed easily, for example by an externalpressure applied in a pressing step during production of the layeredproduct or in various applications of the layered product, for examplein a process for mounting the layered product as an electronic componentin a circuit board. On the other hand, if the curing degree is largerthan these ranges, problems such as cracking may arise in the case wherea cylindrical continuous layered product is removed from a can roller inthe production process of the layered product, which will be describedlater, in the case where a flat layered base element is obtained bypressing, or in the case an external pressure is applied in variousapplications of the layered product, for example in a process formounting the layered product as an electronic component.

The protective layer can be colored to a specific color. This allows animprovement in accuracy of pattern recognition when mounting the layeredproduct on a printed circuit board as an electronic component orfacilitates the identification of each product. For example, coloringcan be performed by mixing a colorant such as a pigment or coating theouter surface with a paint. Moreover, the protective layer can be madetransparent, if necessary.

The layered product of the present invention can be used in variousapplications. It is preferable to form external electrodes on oppositesides of the layered product when it is used as an electronic component,especially as a capacitor.

FIG. 11 is a schematic perspective view illustrating an example of achip capacitor produced by using the layered product of the presentinvention provided with external electrodes.

In this example, reinforcement layers 102 a and 102 b are deposited onboth surfaces of a layered product portion 101 where a plurality ofdeposition units, each of which comprises a resin thin film layer and ametal thin film layer, are deposited. Further, protective layers 103 aand 103 b are deposited on both surfaces thereof. External electrodes104 a and 104 b are formed on the opposite both sides thereof.

In the case the layered product portion 101 takes the deposition formshown in FIG. 1 or 3, the first metal thin film layer and the secondmetal thin film layer are electrically connected to the externalelectrodes 104 a and 104 b, respectively. In the case the layeredproduct portion 101 takes the deposition form shown in FIG. 4 or 6, themetal thin film layers of adjacent deposition units are electricallyconnected alternately to the external electrodes 104 a and 104 b.Similarly, in the case the reinforcement layers 102 a and 102 b take thedeposition form shown in FIG. 7 or 8, the first metal layer and thesecond metal layer are electrically connected to the external electrodes104 a and 104 b, respectively. In the case the reinforcement layers 102a and 102 b take the deposition form shown in FIG. 9 or 10, the metallayer is electrically connected to either one of the external electrodes104 a and 104 b.

The external electrodes can be formed by metal spraying with brass orthe like. In addition, the external electrodes can be constituted of aplurality of layers. For example, an underlying layer that is to beelectrically connected to the metal thin film layer of the layeredproduct portion 101 is formed by metal spraying and another layer isprovided thereon by a method such as metal spraying, plating or coating.More specifically, a metal having good adhesion strength with thelayered product can be selected to form the underlying layer, and ametal having good adhesiveness with various metals or a resin to becontacted (deposited) further thereon can be selected to form the upperlayer.

Furthermore, for a soldering property at the time of mounting, meltsolder plating, melt tinning, electroless solder plating or the like canbe performed. In this case, as an underlying layer, the following layercan be formed: a layer obtained by applying a conductive paste wherecopper powder or the like is dispersed in a thermosetting phenol resinand heating for curing; or a layer obtained by spraying a metal such asan alloy comprising copper/phosphorus/silver.

Furthermore, a bump electrode can be provided in the external electrodeto facilitate the mounting onto a circuit board further. The bumpelectrode can be formed by selecting a material suitably from knownmaterials or shapes.

Furthermore, a necessary outer package in accordance with the intendedapplication can be provided. For example, a coating about several tensof angstroms thick is provided using a surface treatment agent such as asilane coupling agent for the purpose of improving resistance againsthumidity of the layered product or protecting exposed metal thin filmlayers and/or metal layers. Alternatively, a layer obtained by applyinga photocurable or thermosetting resin to a thickness of about severalhundreds μm and curing the resin can be provided.

The layered product of the present invention can be used as a chipcapacitor, a chip coil, a chip resistor, and a composite elementincluding these, and used suitably as an electronic component such as acapacitor. In particular, the layered product of the present inventioncan be a capacitor having high capacitance, although it is small.Therefore, when it is used as a chip capacitor, the practical value ishigh.

Next, a method for producing the layered product of the presentinvention will be described.

FIG. 12 is a schematic view illustrating an example of a productionapparatus for producing the layered product of the present invention.

An apparatus 203 for forming a metal thin film is provided at a lowerportion of a can roller 201, which rotates in the direction of the arrowin FIG. 12 with constant angular velocity or constant circumferentialvelocity. An apparatus 202 for forming a resin thin film is provideddownstream in the rotation direction of the can roller 201.

In this example, an apparatus 208 for applying patterning material isprovided upstream of the apparatus 203 for forming a metal thin film. Anapparatus 209 for removing patterning material is provided between theapparatus 203 for forming a metal thin film and the apparatus 202 forforming a resin thin film. An apparatus 206 for curing resin and anapparatus 207 for treating a resin surface are provided between theapparatus 202 for forming a resin thin film and the apparatus 208 forapplying patterning material. However, these apparatuses can be omittedif desired.

The apparatuses are installed inside a vacuum container 204, in which avacuum is maintained with a vacuum pump 205.

The circumferential surface of the can roller 201 is smooth, preferablymirror-finished, and cooled preferably to −20° C. to 40° C., morepreferably −10° C. to 10° C. The rotation velocity can be adjustedfreely, but preferably is about 15 to 70 rpm.

The apparatus 203 for forming a metal thin film forms a metal thin filmon the surface of the can roller 201. For example, a metal depositionsource can be used. The formed metal thin film forms the metal thin filmlayers of the layered product of the present invention and the metallayers of the reinforcement layer. As the deposition metal, for example,at least one selected from the group consisting of Al, Cu, Zn, Sn, Au,Ag, and Pt can be used. Instead of deposition, the metal thin film canbe formed by a known technique such as sputtering, ion plating or thelike.

The apparatus 202 for forming a resin thin film evaporates and vaporizesa reactive monomer resin toward the surface of the can roller 201. Theresin is deposited so as to form the resin thin film layers of thepresent invention, the resin layers of the reinforcement layer and theprotective layer.

FIG. 13 is a schematic view illustrating the internal structure of theapparatus 202 for forming a resin thin film shown in FIG. 12.

A liquid reactive monomer for forming the resin thin film layer isintroduced through a raw material supply tube 211, and dripped onto aheating plate A 212 that is provided with a tilt inside the apparatus202 for forming a resin thin film. The reactive monomer is heated whilemoving downward on the heating plate A 212. A portion of the reactivemonomer evaporates, whereas the portion of the reactive monomer that hasnot evaporated drops onto a heating drum 213, which rotates at apredetermined rotational speed. A portion of the reactive monomer on theheating drum 213 evaporates, whereas the portion of the reactive monomerthat has not evaporated drops onto a heating plate B 214. While thereactive monomer moves downward on the heating plate B 214, a portionthereof evaporates and the portion of the reactive monomer that has notevaporated drops onto a heating plate C 215. While the reactive monomermoves downward on the heating plate C 215, a portion thereof evaporatesand the portion of the reactive monomer that has not evaporated dropsinto a heated cup 216. The reactive monomer in the cup 216 evaporatesgradually. The vapor reactive monomer that has evaporated in theabove-described manner forms goes up inside a surrounding wall 218,passes between shielding plates 217 a, 217 b and 217 c, and reaches thecircumferential surface of the can roller 201, where the monomercondenses and solidifies to form the resin thin film layer. The meansfor evaporating the reactive monomer is not limited to the abovestructure, and can be changed as appropriate.

The resin thin film layer of the present invention is formed bycondensing the evaporated reactive monomer on the can roller 201, sothat a resin thin film layer having a smooth surface can be obtained.More specifically, in the present invention, it is not at all requiredto contain a protrusion forming component, which is contained in aconventional resin thin film layer (resin film) obtained by melting aresin material and stretching the same for the purpose of providing asmoothing property. Moreover, in a conventional resin thin film layerobtained by applying a solution of a resin material diluted with asolvent to a supporting base and drying and curing the resin material,defects such as large protrusions are formed on the surface in theprocess of evaporation of the solvent. However, since the presentinvention contains no solvent, such defects are not generated.

Furthermore, in order to form a resin thin film layer having an evensmoother surface, it is preferable to provide the shielding plates 217a, 217 b, and 217 c in the path where the evaporated reactive monomerreaches the can roller 201. The reason for this is as follows: Theliquid reactive monomer supplied by the raw material supply tube 211sometimes is heated abruptly by the heating plate A 212, so that largeparticles may develop and scatter. By employing the shielding platesthat prohibit the reactive monomer from passing straight from the pointof evaporation to the point of adherence on the surface of the canroller, the adherence of large particles can be greatly reduced, so thatthe surface of the resin thin film layer becomes very smooth.Consequently, as long as the shielding plates serve this end, there isno particular limitation to the shape and arrangement shown in FIG. 13.

Furthermore, in order to form a resin thin film layer having a smoothsurface, it is preferable to charge the evaporated reactive monomerand/or the surface of adherence.

In the apparatus for forming a resin thin film shown in FIG. 13, adevice 219 for irradiating a charged particle beam is provided at apassing point of the reactive monomer. The charged monomer particles areaccelerated by electrostatic attraction, and due to the microscopicelectrostatic repulsion during the deposition, they avoid the portionswhere charged particles already were deposited. Due to this mechanism, avery smooth resin film layer can be formed.

The device for irradiating a charged particle beam also can be providedfacing the deposition surface of the reactive monomer. FIG. 14 is aschematic view illustrating an example of an apparatus for producing alayered product having such a structure. A device 220 for irradiating acharged particle beam is provided downstream from the apparatus 209 forremoving patterning material, which is described later, and upstreamfrom an apparatus 202′ for forming a resin thin film, facing thecircumferential surface of the can roller 201. In this case, theapparatus 202 for forming a resin thin film provided with the device forirradiating a charged particle beam as shown in FIG. 13 can be used asthe apparatus for forming a resin thin film.

Any device for irradiating a charged particle beam can be used, as longas it confers an electrostatic charge to the reactive monomer particlesor to the deposition surface. For example, an electron beam irradiationdevice, an ion source irradiating an ion beam, or a plasma source can beused.

Since the metal thin film layers of the present invention are very thin,the shape of the underlying layers on which the metal thin film layersare formed is reflected by the surface of the metal thin film layers. Itfollows that since the surfaces of the resin thin film layers formed asdescribed above are very smooth, the surfaces of the metal thin filmlayers formed thereon also are very smooth.

If necessary, the deposited reactive monomer resin is polymerized and/orcross-linked with the apparatus 206 for curing resin and cured to apredetermined curing degree. As the apparatus for curing resin, anelectron beam irradiation device or a UV beam irradiation device can beused, for example.

If necessary, the surface of the formed resin thin film layer is treatedwith the apparatus 207 for treating a resin surface. For example, thesurface of the resin thin film layer can be activated with an oxygenplasma to increase the adhesiveness with the metal thin film.

The apparatus 208 for applying patterning material is used to depositthe metal thin film layer only in a specific area rather than on theentire surface of the resin thin film layer. The apparatus 208 forapplying patterning material deposits a patterning material on thesurface of the resin thin film in a belt-shape in the direction of thecircumference of the can roller 201. At the portions where thepatterning material has been deposited, no metal thin film is formed, sothat these portions become, for example the electrically insulatingportions and the electrically insulating bands of the reinforcementlayer. As the patterning material, for example, oil can be used. Toapply the patterning material, evaporated and vaporized patterningmaterial can be ejected from pinholes and condensed on the surface ofthe resin thin film, or liquid patterning material can be ejected.Besides these examples of contactless application methods, otherapplication methods such as reverse coating or die coating are possible,but for the present invention, contactless application methods arepreferable because no external pressure is applied to the resin surface.Especially, a method of condensing the evaporated patterning material onthe surface of the resin thin film is preferable because the structureis relatively simple.

FIG. 15 is a schematic front view of an apparatus for applyingpatterning material that applies a belt-shaped oil film on a surface ofa resin thin film by ejecting evaporated oil as an example of theapparatus for applying patterning material. On the front of theapparatus for applying patterning material, a predetermined number ofpinholes 231 are arranged at predetermined intervals. The apparatus 208for applying patterning material is positioned in a manner that thepinholes 231 oppose the circumferential surface of the can roller 201,and the direction indicated by arrow 232 matches the travel direction ofthe circumferential surface of the can roller 201. Then, the evaporatedpatterning material is ejected from the pinholes 231 so as to depositthe patterning material on the resin thin film layer on the can roller,and condensed by cooling, whereby a deposition film of the patterningmaterial is formed. Consequently, the interval and the number ofpinholes 231 correspond to the interval and the number of theelectrically insulating portions (or electrically insulating bands)formed on the resin thin film layer. The shape of the pinholes 231 canbe round, as shown in FIG. 15, but elliptical, elongated, rectangular orother shapes are also possible. Alternatively, a plurality ofelliptical, elongated, or rectangular pinholes can be arranged in thetravel direction of the surface of the can roller.

The patterning material applied with the apparatus 208 for applyingpatterning material can be removed by an apparatus 209 for removingpatterning material, if necessary. When the patterning material remains,the following problems arise. The surfaces of the resin thin film layerand the metal thin film layer chap so that a layered product having thesurface roughness of the present invention cannot obtained. A pin-hole(lack of deposition) in the resin thin film layer or the metal thin filmlayer is generated. The electrically insulating portions (orelectrically insulating bands) having a predetermined width cannot beformed stably. There is no particular limitation regarding how thepatterning material is removed. However, for example, when oil is usedas the patterning material, the patterning material can be removed byheat evaporation by a heater, or decomposition by plasma irradiation, ora combination thereof. In this case, oxygen plasma, argon plasma,nitrogen plasma, or the like can be used for the plasma irradiation, butamong these, oxygen plasma is most preferable.

Thus, a layered product where a predetermined number of depositionunits, each of which comprises a resin thin film layer and a metal thinfilm layer, are deposited on the circumferential surface of the canroller 201 can be obtained by rotating the can roller 201. In order toform the layered product shown in FIGS. 1, 3, 4 and 6, it is required tomove the deposition position of the patterning material by apredetermined distance in the direction perpendicular to the traveldirection of the circumferential surface of the can roller 201 for thepurpose of changing the position of the electrically insulating portion,every time one deposition unit comprising a resin thin film layer and ametal thin film layer is deposited. Similarly, in order to form thereinforcement layer shown in FIGS. 8 and 10, it is required to move thedeposition position of the patterning material by a predetermineddistance in the direction perpendicular to the travel direction of thecircumferential surface of the can roller 201 for the purpose ofchanging the position of the electrically insulating band, every timeone deposition unit comprising a resin layer and a metal layer isdeposited.

Furthermore, in the process of producing the layered product, since thedeposition thickness is larger as the deposition units are depositedsequentially, it is preferable to retract the apparatus 208 for applyingpatterning material as the deposition progresses, not only in the casewhere the patterning material is directly applied by coating or the likebut also in the case where deposition is performed by a contactlessmethod. In other words, in FIG. 12, it is preferable to deposit layerswhile maintaining a constant distance Dn between the circumferentialsurface of the layered product that is being formed on the can roller201 and the pinhole end of the apparatus for applying patterningmaterial at a predetermined interval. This is because the patterningmaterial diffuses with a certain directivity especially when vaporizedoil is ejected for deposition, so that a variation of the distance Dnchanges the deposition width, whereby the electrically insulatingportion having a predetermined width cannot be obtained stably.

The retraction of the apparatus for applying patterning material and themovement of the deposition position of the patterning material can beperformed, for example by an apparatus as shown in FIG. 16.

First, the apparatus for applying patterning material is retracted inthe following manner. An actuator A 302 is fixed on a movable base 301.The apparatus 208 for applying patterning material is attached to themobile end of the actuator A 302. The actuator A 302 can move theapparatus 208 for applying patterning material in the direction of arrow303 on the movable base 301. A gap measuring device 304 for measuringthe distance to the surface of the can roller 201 (the circumferentialsurface of the layered product in the process of the formation of thelayered product) is provided on the apparatus 208 for applyingpatterning material. A contactless measuring device, for example ameasuring device using a laser, can be used for the gap measuring device304. During the manufacturing of the layered product, the gap measuringdevice 304 keeps measuring the distance to the circumferential surfaceof the layered product on the surface of the can roller 201, and asignal corresponding to this measurement is sent to a gap measuringcircuit 305. The gap measuring circuit 305 continuously checks whetherthe distance between the pinhole end of the apparatus 208 for applyingpatterning material and the surface of the can roller 201 (thecircumferential surface of the layered product in the process of theformation of the layered product) is within a predetermined range. Whenthe deposition progresses and the gap measuring circuit 305 determinesthat this distance is smaller than the predetermined range, it instructsthe actuator A 302 to retract the apparatus 208 for applying patterningmaterial a predetermined distance, and based on this instruction, theapparatus 208 for applying patterning material is retracted apredetermined distance. Thus, the distance Dn between the pinhole end ofthe apparatus 208 for applying patterning material and thecircumferential surface of the layered product on the can roller 201always can be kept within a constant interval while the depositionprogresses.

As an alternative to the control using the gap measuring device 304 andthe gap measuring circuit 305 as described above, the apparatus forapplying patterning material also can be retracted for a preset lengththat is based on the layering thickness, in accordance with the numberof rotations of the can roller 201 (for example, per rotation).Moreover, a fine-tuning mechanism of verifying the actual distance withthe gap measuring device 304 described above can be added to thisconfiguration

Next, the position where the patterning material is applied can bemodified in the following manner. An actuator B 307 is attached to asupport base 306. The movable base 301 is attached to the mobile end ofthe actuator B 307. The actuator B 307 can move the movable base 301 onthe support base 306 in the direction indicated by arrow 308. Therotation of the can roller 201 is observed by a rotation detector (notshown in the drawing), which sends a rotation signal S1 to a rotationdetecting circuit 309 whenever the can roller 201 has rotated one turn.When the rotation detecting circuit 309 has counted a predeterminednumber of detections of the rotation signal S1 (for example onedetection), it instructs the actuator B 307 to move the movable base 301for a predetermined distance in a predetermined direction as indicatedby arrow 308. Thereby, the movable base 301, and thus the apparatus 208for applying patterning material, is moved a predetermined distance in apredetermined direction as indicated by arrow 308. Thus, the positionwhere patterning material is applied can be changed for everypredetermined number of rotations of the can roller 201 for apredetermined distance in a direction that is perpendicular to therotation and travel direction of the surface of the can roller 201.

In this manner, the layered product where a plurality of depositionunits, each of which comprises a resin thin film layer and a metal thinfilm layer, are deposited is formed on the circumferential surface ofthe can roller 201. For forming a layer comprising no metal thin filmlayer, such as the protective layer, only resin can be deposited withthe apparatus 202 for forming a resin thin film by rotating the canroller 201 until a predetermined thickness is formed, while providingshielding plates or the like to prevent the apparatus 203 for forming ametal thin film and the apparatus 208 for applying patterning materialfrom functioning. Similarly, for forming only metal thin film layerssuccessively, only metal thin film layers can be deposited by rotatingthe can roller 201 until a predetermined thickness is formed whileproviding shielding plates or the like to prevent the apparatus 202 forforming a resin thin film from functioning.

Thus, a cylindrical continuous product of a layered product is formed onthe circumferential surface of the can roller 201. This is divided inthe radial direction (e.g., into 8 sections by every 45°) and removedfrom the can roller 201. The sections are pressed under heat andpressure, and flat layered base elements are obtained. Thereafter, thelayered base elements are cut or provided with an outer package, ifnecessary, depending on the intended application of the layered product.

The present invention will be described by taking the production of achip capacitor from the layered product of the present invention as anexample.

FIG. 17 is a partial perspective view illustrating an example of theoutline of the structure of the flat layered base element obtained inthe above-described manner. In FIG. 17, arrow 401 indicates the traveldirection (circumferential direction) on the can roller 201.

The layered base element 400 in FIG. 17 includes a protective layer 404b, a reinforcement layer 403 b, a layered product portion 402 comprisingresin thin film layers and metal thin film layers, a reinforcement layer403 a and a protective layer 404 a, which are deposited on the canroller 201 in this order.

Thereafter, the layered base element is cut along cutting planes 405 aand external electrodes are formed at the cutting planes, and further iscut along planes corresponding to cutting planes 405 b, so that a chipcapacitor as shown in FIG. 11 can be obtained. In the chip capacitor inthis example, the layered product portion 402 has the structure in FIG.1, and each of the reinforcement layers 403 a and 403 b has thestructure in FIG. 7.

A chip capacitor having a different deposition form can be obtained bysuitably changing the position on which patterning material is appliedand the positions of the cutting planes 405 a. For example, as shown inFIG. 18, a chip capacitor as shown in FIG. 11 can be obtained by cuttingalong cutting planes 405 a′ a layered base element 400′ where aprotective layer 404 b′, a reinforcement layer 403 b′, a layered productportion 402′ comprising resin thin film layers and metal thin filmlayers, a reinforcement layer 403 a′ and a protective layer 404 a′ aredeposited sequentially, forming external electrodes at the cuttingplanes and further cutting it along planes corresponding to cuttingplanes 405 b′. In the chip capacitor in this example, the layeredproduct portion 402′ has the structure in FIG. 4, and each of thereinforcement layers 403 a′ and 403 b′ has the structure in FIG. 9.

Although in the apparatus in FIG. 12, the layered product is formed onthe cylindrical can roller 201, the supporting base on which the layeredproduct is formed is not limited thereto. For example, the layeredproduct can be formed on a belt-shaped supporting base 221 that rotatesalong two rolls as shown in FIG. 19. The belt-shaped supporting base 221can be formed of a metal, a resin, a fabric or a complex of these.Numeral 202″ denotes an apparatus for forming a resin thin film, andthis apparatus differs from the apparatus 202 for forming a resin thinfilm shown in FIG. 12 only in the shape of the surrounding wall.

In addition, a rotating disk can be used as the supporting base. In thiscase, the electrically insulating portions are formed concentrically.

Hereinafter, the first invention of the present invention will bedescribed more specifically by way of examples.

EXAMPLE 1

A chip capacitor as shown in FIG. 11 was produced with the apparatusshown in FIG. 12.

The production method thereof is as follows.

A vacuum container 204 was evacuated to 2×10⁻⁴ Torr, and thecircumferential surface of the can roller 201 was maintained at 5° C.

First, a portion that is to serve as the protective layer was depositedon the circumferential surface of the can roller 201. Dimethyloltricyclodecane diacrylate was used as the material of the protectivelayer, and evaporated so as to be deposited on the circumferentialsurface of the can roller 201 with the apparatus 202 for forming a resinthin film. The apparatus for forming a resin thin film used was thatshown in FIG. 13, and an electron beam irradiation device was used asthe device for irradiating a charged particle beam. The drivingcondition was 3 kV 2 mA. Then, a UV curing device was used as theapparatus 206 for curing resin to polymerize and cure the protectivelayer material deposited in the above-described manner. This operationwas repeated by rotating the can roller 201 so that the protective layerhaving a thickness of 15 μm was formed on the circumferential surface ofthe can roller 201.

Then, a portion that is to serve as the reinforcement layer wasdeposited. The same material as that for the protective layer was usedas the resin layer material, and evaporated so as to be deposited on theprotective layer with the apparatus 202 for forming a resin thin film.The apparatus for forming a resin thin film used was that shown in FIG.13, and an electron beam irradiation device was used as the device forirradiating a charged particle beam. The driving condition was 3 kV 2mA. Then, a UV curing device was used as the apparatus 206 for curingresin to polymerize and cure the resin layer material deposited in theabove-described manner. The thickness of the thus formed resin layer was0.4 μm. Thereafter, the surface was treated with oxygen plasma with theapparatus 207 for treating resin surface. Next, a pattering material wasapplied in a portion corresponding to the electrically insulating bandwith the apparatus 208 for applying pattering material. A fluorocarbonoil was used as the pattering material, and evaporated and ejected frompinholes having a diameter of 50 μm so as to be deposited in the form ofa belt having a width of 150 μm. Then, aluminum was deposited with theapparatus 203 for forming a metal thin film. The deposition thicknesswas 300 Å, and the film resistance was 3Ω/□. Thereafter, the residualpatterning material was removed by heating with a far infrared radiationheater and a plasma discharge treatment using the apparatus 209 forremoving patterning material. This operation was repeated 500 times byrotating the can roller 201 so that the reinforcement layer having atotal thickness of 215 μm was formed. The movement of the apparatus forapplying patterning material in the direction perpendicular to thetravel direction of the circumferential surface of the can roller 201(the direction indicated by arrow 308 in FIG. 16) was performed with thedevice shown in FIG. 16 in the following pattern. The apparatus wasallowed to move 60 μm in one direction when the can roller 201 hadrotated one turn, and after the next rotation, the apparatus was allowedto move 60 μm in the reverse direction to return to the originalposition. This operation was repeated thereafter. The distance Dnbetween the pinholes 231 of the apparatus for applying patterningmaterial and the adherence surface was controlled to be maintainedconstantly at 250 to 300 μm.

Next, the layered product portion comprising resin thin film layers andmetal thin film layers was deposited. The same material as that for theprotective layer and the resin layer was used as the resin thin filmlayer material, and evaporated so as to be deposited on thereinforcement layer. The apparatus for forming a resin thin film usedwas that shown in FIG. 13, and an electron beam irradiation device wasused as the device for irradiating a charged particle beam. The drivingcondition was 3 kV 2 mA. Then, a UV curing device was used as theapparatus 206 for curing resin to polymerize and cure the resin thinfilm layer material deposited in the above-described manner. Thethickness of the thus formed resin thin film layer was 0.4 μm.Thereafter, the surface was treated with oxygen plasma with theapparatus 207 for treating resin surface. Next, a pattering material wasapplied in a portion corresponding to the electrically insulatingportion with the apparatus 208 for applying pattering material. Afluorocarbon oil was used as the pattering material, and evaporated andejected from pinholes having a diameter of 50 μm so as to be depositedin the form of a belt having a width of 0.15 mm. Then, aluminum wasdeposited with the apparatus 203 for forming a metal thin film. Thedeposition thickness was 250 Å, and the film resistance was 6Ω/□.Thereafter, the residual patterning material was removed by heating witha far infrared radiation heater and a plasma discharge treatment usingthe apparatus 209 for removing patterning material. This operation wasrepeated 2000 times by rotating the can roller 201 so that the layeredproduct portion having a total thickness of 850 μm was formed. Themovement of the apparatus for applying patterning material in thedirection perpendicular to the travel direction of the circumferentialsurface of the can roller 201 (the direction indicated by arrow 308 inFIG. 16 was performed with the device shown in FIG. 16 in the followingpattern. When the can roller 201 had rotated one turn, the apparatus wasallowed to move 1000 μm in one direction, and after the next rotation,the apparatus was allowed to move 1000 μm in the reverse direction toreturn to the original position. This operation was repeated thereafter.The distance Dn between the pinholes 231 of the apparatus for applyingpatterning material and the adherence surface was controlled to bemaintained constantly at 250 to 300 μm.

Next, a reinforcement layer portion having a thickness of 215 μm wasformed on a surface of the element layer portion. The method thereof wasexactly the same as the method for the reinforcement layer as describedabove.

Finally, a protective layer portion having a thickness of 15 μm wasformed on a surface of the reinforcement layer. The method thereof wasexactly the same as the method for the protective layer as describedabove.

Then, the obtained cylindrical layered product was cut into 8 sectionsin the radial direction (separated by 45°) and removed. The sectionswere pressed under heat, and flat layered base elements as shown in FIG.17 were obtained. The flat layered base elements were cut along thecutting planes 405 a, and the cutting planes were metallized with brassso as to form external electrodes. An electrically conducting pastewhere copper powder had been dispersed in a thermosetting phenol resinwas applied to the metallized surface, heat-cured, and the resultingresin surface was plated with molten solder. After that, the pieces werecut along the cutting planes 405 b in FIG. 17, and immersed in a silanecoupling agent to coat the circumferential surface, whereby chipcapacitors as shown in FIG. 11 were obtained. In the obtained chipcapacitor in FIG. 11, the layered product portion 101 had the depositionform in FIG. 1, and the reinforcement layer portions 102 a and 102 b hadthe deposition form in FIG. 7.

The obtained chip capacitor was dismantled, and the surface roughnessesof the surface of the resin thin film layer deposited on the metal thinfilm layer of the layered product portion 101, the surface of the resinthin film layer deposited on the electrically insulating portion, andthe surface of the metal thin film layer were measured. The results were0.005 μm, 0.008 μm, and 0.005 μm, respectively. The width of theelectrically insulating portion was 150 μm, and the displacement amountd in the deposition position of the electrically insulating portion ofevery other deposition unit was substantially zero. The width of theelectrically insulating band of the reinforcement layer was 150 μm andwas positioned substantially in the center in the width direction, andthe displacement amount d1 in the deposition position of theelectrically insulating band of every other adjacent deposition unit wassubstantially zero. The curing degrees of the resin thin film layer oflayered product portion, the resin layer of the reinforcement layer andthe protective layer were 95%, 95% and 90%, respectively.

The obtained chip capacitor had a thickness in the deposition directionof 1.3 mm, a depth of 1.6 mm and a width (in the direction between theopposite external electrodes) of 3.2 mm, which was small, and yet thecapacitance was 0.47 μF. The insulation resistance was 7.5×10¹⁰Ω, andthe withstand voltage was 48V. Furthermore, slight roughness wasobserved on the upper and lower surfaces in the deposition direction.This was mounted onto a printed circuit board with a solder. There wasno problems such as the external electrodes falling off.

EXAMPLES 2 TO 5, COMPARATIVE EXAMPLE 1

Chip capacitors were produced in the same manner and with the sameapparatuses as those of Example 1, but by changing the material of theresin thin film layer, the deposition thickness, and the driveconditions of the electron beam irradiation device to those shown inTable 1. In Example 3, in addition to the production conditions shown inTable 1, the apparatus for forming a resin thin film was not providedwith the shielding plates 217 a, 217 b, and 217 c. Table 1 also showsthe characteristics of the obtained chip capacitors.

TABLE 1 Resin thin film Surface roughness Characteristics of layer Drivecondition Ra (μm) capacitor Deposition of electron beam Resin MetalInsulation thickness irradiation thin film thin film resistancewithstand Material (μm) device layer layer (Ω) voltage (V) Ex. 1 #1 0.43kV2mA 0.10 0.10 7.5 × 10¹⁰ 48 Ex. 2 #1 0.4 3kV5mA 0.04 0.04 3.0 × 10¹¹55 Ex. 3 #1 0.4 3kV5mA 0.04 0.04 4.5 × 10⁸ 35 Ex. 4 #1 0.4 3kV20mA 0.010.01 2.3 × 10¹² 70 Ex. 5 #2 0.4 (absence) 0.04 0.04 3.3 × 10¹¹ 60 Com.Ex. 1 #1 0.4 (absence) 0.12 0.12 3.0 × 10⁶  8 Note: Resin thin filmlayer materials #1: Dimethylol tricyclodecane diacrylate (viscosity:about l50 cps) #2: 1.9 nonane diol diacrylate (viscosity: about 10 cps)

As shown in Table 1, the layered product of Comparative Example 1 wherethe reactive monomer, which was the resin thin film layer material, wasnot charged, had large surface roughnesses of the resin thin film layerand the metal thin film layer, resulting in poor insulation resistanceand withstand voltage when it was applied to a capacitor.

On the other hand, in some cases as Example 5, a layered product whosesurface roughnesses of the resin thin film layer and the metal thin filmlayer are in the ranges of the present invention can be obtained withoutcharging the reactive monomer, depending on the resin type, for examplea different viscosity. In this case, the insulation resistance andwithstand voltage were good when it was applied to a capacitor.

When the drive condition of the electron beam irradiation device wasmade increasingly larger from Examples 1, 2 and 4 in this order, thesurface roughnesses of the resin thin film layer and the metal thin filmlayer became smaller in this order. This may be because a larger drivecondition results in a larger amount of the reactive monomer charged.This results in improved insulation resistance and withstand voltagewhen it was applied to a capacitor.

Furthermore, in the layered product of Example 3, which was producedwithout the shielding plates of the apparatus for forming a resin thinfilm, although the surface roughnesses (Ra) of the resin thin film layerand the metal thin film layer were in the ranges of the presentinvention, abnormal protrusions were formed, resulting in slightly poorinsulation resistance and withstand voltage when it was applied to acapacitor.

Regarding the Second Invention

Hereinafter, the second aspect of the present inventions will bedescribed with reference to the accompanying drawings.

FIGS. 20 and 21 are perspective views showing the outline of thestructure of the deposition of the layered product of the presentinvention.

A first layered product of the present invention comprises an elementlayer 502, reinforcement layers 503 a and 503 b deposited on both sidesof the element layer, and protective layers 504 a and 504 b depositedfurther on both sides of the reinforcement layers, as shown in FIG. 20.

A second layered product of the present invention comprises an elementlayer 506, and reinforcement layers 507 a and 507 b deposited on bothsides of the element layer, as shown in FIG. 21.

(Element Layer)

The element layers 502 and 506 function as capacitance generationportions where electrostatic charges are stored when the layered productis used as a capacitor. Therefore, the element layers 502 and 506 arerequired to have either one of the structures A and B described below.

A: A plurality of deposition units, each of which comprises a dielectriclayer, a first metal thin film layer and a second metal thin film layerthat are deposited on one surface of the dielectric layer and separatedby a belt-shaped electrically insulating portion, are deposited in sucha manner that the electrically insulating portions of adjacentdeposition units are deposited in different positions.

B: A plurality of deposition units, each of which comprises a dielectriclayer and a metal thin film layer that is deposited on one surface ofthe dielectric layer and in a portion except a belt-shaped electricallyinsulating portion on one end of the surface of the dielectric layer,are deposited in such a manner that the electrically insulating portionsof adjacent deposition units are positioned in the opposite sides.

FIG. 22 is a cross-sectional view taken in the thickness direction(deposition direction) schematically illustrating an example of anelement layer having the structure A.

An element layer 510 comprises a plurality of deposition units 515, eachof which comprises a dielectric layer 511, a first metal thin film layer512 and a second metal thin film layer 514, that are deposited on thedielectric layer 511. The first metal thin film layer 512 and the secondmetal thin film layer 514 are separated by a belt-shaped electricallyinsulating portion 513.

Furthermore, the deposition positions of the electrically insulatingportions of adjacent deposition units are required to be different fromeach other. More specifically, as shown in FIG. 22, in the case wherethe deposition unit 515 is deposited adjacent to a deposition unit 515a, the electrically insulating portion 513 of the deposition unit 515 isrequired to be different in the deposition position from an electricallyinsulating portion 513 a of the deposition unit 515 a. Thus,sequentially depositing the deposition units having different positionsof their electrically insulating portions and forming externalelectrodes on sides of the layered product produces a capacitor (seeFIG. 33). More specifically, an external electrode (not shown) thatconnects in substantially the same potential between the first metalthin film layer 512 of the deposition unit 515 and the first metal thinfilm layer 512 a of the deposition unit 515 a adjacent thereto, and anexternal electrode (not shown) that connects in substantially the samepotential between the second metal thin film layer 514 of the depositionunit 515 and the second metal thin film layer 514 a of the depositionunit 515 a adjacent thereto are provided, and a potential difference isprovided between the opposite external electrodes. In this case, theelectrically insulating portions 513 and 513 a of the deposition unit515 and the deposition unit 515 a adjacent thereto are located indifferent positions so as to form a capacitor having the first metalthin film layer 512 of the deposition unit 515 and the second metal thinfilm layer 514 a of the deposition unit 515 a as electrodes and aportion sandwiched by the first metal thin film layer 512 and the secondmetal thin film layer 514 a of the dielectric layer 511 a as adielectric (capacitance generation portion). Therefore, the phase, “thedeposition positions of the electrically insulating portions of adjacentdeposition units are different” means that the deposition positions aredifferent to the extent that allows the capacitance generation portionof the capacitor to be formed as described above. In such a situation,it is preferable to provide the electrically insulating portion in sucha manner that the area of the capacitance generation portion becomes aslarge as possible.

In the above example, portions other than the portion sandwiched by thefirst metal thin film layer 512 and the second metal thin film layer 512a of the dielectric layer 511 a do not contribute to the formation ofthe capacitance of the capacitor. Moreover, the second metal thin filmlayer 514 of the deposition unit 515 and the first metal thin film layer512 a of the deposition unit 515 a do not function as the electrodes ofthe capacitor. However, the second metal thin film layer 514 of thedeposition unit 515 and the first metal thin film layer 512 a of thedeposition unit 515 a are significant to improve the adhesion strengthof the external electrodes. In other words, the adhesion strengthdepends significantly on the connection strength with the metal thinfilm layers, and the connection strength with the dielectric layers doesnot contribute very much. Therefore, although the metal thin film layersdo not contribute to the capacitance generation of the capacitor, thepresence of the metal thin film layers improves the adhesion strength ofthe external electrodes significantly when the layered product isapplied to the capacitor. The presence of such metal thin film layers isparticularly significant in the case of a small layered product, whichis intended by the present invention. The external electrodes are formedby metal spraying or the like. The particles of a sprayed metal in thiscase are relatively large and hardly penetrate between the metal thinfilm layers in the case of the layered product having very thindielectric layers as in the present invention. In addition, since thelayered product is small, an exposed metal thin film layer portion isvery small. Therefore, it is very significant to make the contact areawith the external electrodes as large as possible for the purpose ofobtaining the adhesion strength of the external electrodes.

The shape of the electrically insulating portion is a belt shape havinga constant width W for ease of the production. FIG. 23 is across-sectional view taken along line III—III viewed from the directionof the arrow in FIG. 22. The width W of the electrically insulatingportion is not limited to a particular value, but preferably is about0.03 to 0.5 mm, more preferably about 0.05 mm 0.4 mm and most preferablyabout 0.1 to 0.3 mm. When the width is larger than these ranges, thearea of the capacitance generation portion for a capacitor becomessmall, so that high capacitance cannot be achieved. On the other hand, awidth smaller than these ranges makes it difficult to obtain theelectrical insulation or to produce a narrow electrically insulatingportion precisely.

In the case where the element layer has the structure A, it ispreferable that the deposition position of the electrically insulatingportions of every other deposition unit of the element layer is the sameposition over the element layer. FIG. 24 is a cross-sectional view takenin the thickness direction (deposition direction) schematicallyillustrating an example of the element layer having such a structure.More specifically, with respect to an electrically insulating portion523 of a deposition unit 525, the position of an electrically insulatingportion 523 b of a deposition unit 525 b, which is one unit apart fromthe deposition unit 525, is not the same position as that of theelectrically insulating portion 523, but is displaced by d in the widthdirection of the electrically insulating portion. Then, in the samemanner, the position of the electrically insulating portion of thedeposition unit that is one unit further apart is displaced by d ineither direction in the width direction of the electrically insulatingportion. Alternatively, the position of the electrically insulatingportion of the deposition unit one unit apart is in the same position,and the position of the electrically insulating portion of thedeposition unit three units apart can be displaced in the widthdirection of the electrically insulating portion.

Such displacement of the deposition position of the electricallyinsulating portion can suppress roughness of the upper and lowersurfaces of the element layer, and thus roughness of the upper and lowersurfaces of the layered product. In other words, since there are nometal thin film layers in the electrically insulating portion, thethickness of the deposition of this portion is smaller relative to theoverall element layer, so that a recess is generated in portions 526 aand 626 b on the upper surface of the element layer. This recess maydeteriorate the handling properties when mounting the layered productonto a printed circuit board with a solder and may adversely affect thewettability of the solder. In addition, when such a recess is generated,the larger the depth of the recess is, the more difficult it is to applya patterning material onto the bottom of the recess as described laterin the production process of the layered product. Therefore, it isdifficult to form a good electrically insulating portion having aconstant width. Moreover, the generation of the recess causesinclination of the dielectric layer and the metal thin film layerdeposited on the recess at both sides of the electrically insulatingportion, so that the thickness of the deposition of the dielectric layerand the metal thin film layer becomes small locally. When the thicknessof the deposition of the dielectric layer becomes small locally, thefollowing problem arises. In the case where the layered product is usedas a capacitor, the presence of that portion reduces the withstandvoltage of the capacitor and causes a short-circuit due to a pin-hole inthe dielectric layer. Moreover, when the thickness of the deposition ofthe metal thin film layer becomes small locally, poor conductivity islikely to occur in that portion.

FIG. 25 is a cross-sectional view taken in the thickness direction(deposition direction) schematically illustrating an example of theelement layer having the structure B.

An element layer 530 comprises a plurality of deposition units 534, eachof which comprises a dielectric layer 531 and a metal thin film layer532 deposited on one surface of the dielectric layer 531. The metal thinfilm layer 532 is not provided in a belt-shaped electrically insulatingportion 533, which is provided on one end of one surface of thedielectric layer 531.

Furthermore, it is required that the electrically insulating portions ofadjacent deposition units are located on the opposite sides. Morespecifically, as shown in FIG. 25, in the case where a deposition unit534 is deposited adjacent to a deposition unit 534 a, and when anelectrically insulating portion 533 of the deposition unit 534 is on theright end of the dielectric layer 531, it is required that anelectrically insulating portion 533 a in the deposition unit 534 a isprovided on the left end of a dielectric layer 531 a. In this manner,the deposition units are deposited sequentially in such a manner thatthe electrically insulating portions are located on the opposite sides.Thus, when external electrodes are formed on the side portions of thelayered product (see FIG. 33), a capacitor can be formed. In otherwords, one external electrode is connected to the metal thin film layer532 of the deposition unit 534, and the other external electrode isconnected to the metal thin film layer 532 a of the adjacent depositionunit 534 a, and an electrical potential difference is provided betweenthe opposite external electrodes. The thus formed capacitor has themetal thin film layer 532 of the deposition unit 534 and the metal thinfilm layer 532 a of the deposition unit 534 a as the electrodes, and aportion sandwiched between the metal thin film layer 532 and the metalthin film layer 532 a as the dielectric (capacitance generationportion). From such a viewpoint, it is preferable that the width of theelectrically insulating portion is as small as possible so as to makethe area of the capacitance generation portion as large as possible.

The shape of the electrically insulating portion is a belt-shape havinga constant width W for ease of the production. FIG. 26 is across-sectional view taken along line IV—IV viewed from the arrowdirection in FIG. 25. The width W of the electrically insulating portionis not limited to a particular value, but preferably is about 0.03 to0.5 mm, more preferably about 0.05 to 0.4 mm, and most preferably about0.1 to 0.3 mm to allow high capacitance of the capacitor, to make surethe electrical insulation and to facilitate the production.

When the element layer has the structure B, it is preferable that allthe widths of the belt-shaped electrically insulator of every otherdeposition unit are not the same over the layered product. FIG. 27 is across-sectional view taken in the thickness direction (depositiondirection) schematically illustrating one example of the element layerhaving such a structure. As shown in FIG. 27, with respect to anelectrically insulating portion 543 of a deposition unit 544, the widthof an electrically insulating portion 543 b of a deposition unit 544 b,which is one unit apart from the deposition unit 544, is different fromthat of the electrically insulating portion 543. Thereafter, in the samemanner, the width of the electrically insulating portion of thedeposition unit that is one unit apart is changed sequentially.Alternatively, the width of the electrically insulating portion is thesame as that of the electrically insulating portion of the depositionunit that is one unit apart, and the width of the electricallyinsulating portion of the deposition unit three units apart can bechanged.

When all the widths of the electrically insulating portions are thesame, the end portion where the electrically insulating portions areprovided has a small number of metal thin film layers. Therefore, thethickness of the deposition of this portion is smaller relative to theoverall layered product so that a significant recess is generated on theupper surface of the layered product. This recess may deteriorate thehandling properties when mounting the layered product onto a printedcircuit board with a solder and may adversely affect the wettability ofthe solder. In addition, when such a recess is generated, the larger thedepth of the recess is, the more difficult it is to apply a patterningmaterial onto the bottom of the recess as described later in theproduction process of the layered product. Therefore, it is difficult toform a good electrically insulating portion having a constant width.Moreover, the generation of the recess causes inclination of thedielectric layer and the metal thin film layer deposited on the recessat a side of the electrically insulating portion, so that the thicknessof the deposition of the dielectric layer and the metal thin film layerbecomes small locally. When the thickness of the deposition of thedielectric layer becomes small locally, the following problem arises. Inthe case where the layered product is used as a capacitor, the presenceof that portion reduces the withstand voltage of the capacitor andcauses a short-circuit due to a pin-hole in the dielectric layer.Moreover, when the thickness of the deposition of the metal thin filmlayer becomes small locally, poor conductivity is likely to occur inthat portion.

It is required to deposit a plurality of deposition units, each of whichcomprise the dielectric layer and the metal thin film, whether theelement layer has the structure A or B. A capacitor is formed bydepositing a plurality of deposition units. The number of depositions ispreferably 100 or more, more preferably 1000 or more, even morepreferably 2000 or more and most preferably 3000 or more. The larger thenumber is, the larger capacitance the capacitor can have when used as acapacitor. Furthermore, since the layered product of the presentinvention has a reinforcement layer and, preferably, a protective layer,even if the dielectric layer is thin, the adhesion strength of theexternal electrodes is high and is sufficiently resistant againstthermal load and external pressure. Therefore, when the thickness of thedielectric layer is thin, the overall thickness is not very large evenif the number of depositions is large. Compared with a conventional filmcapacitor, the thus obtained capacitor has higher capacitance with thesame volume, or is smaller with the same capacitance.

The thickness of the dielectric layer (thickness in the capacitancegeneration portion) T1 (see FIG. 22) or T3 (see FIG. 25) is preferably 1μm or less, more preferably 0.7 μm or less, and most preferably 0.4 μmor less. A smaller thickness of the dielectric layer (capacitancegeneration portion) can provide a capacitor having a larger capacitance.

There is no particular limitation regarding the thickness T2 (see FIG.22) of the first metal thin film layer and the second thin film layer ofthe element layer having the structure A and the thickness T4 (see FIG.25) of the metal thin film layer of the element layer having thestructure B, but it is preferably 50 nm or less, and more preferably 40nm or less. There is no particular limitation regarding the lower limit,but it is preferably at least 10 nm, and more preferably at least 20 nm.Furthermore, the film resistance is preferably 2Ω/□ or more, morepreferably 3Ω/□ or more, and most preferably 5Ω/□ or more. There is noparticular limitation regarding the upper limit, but it is preferably15Ω/□ or less, more preferably 10Ω/□ or less, and most preferably 8Ω/□or less. In the case where the element layer has the structure A, thethickness of the first metal thin film layer can be different from thatof the second metal thin film, but it is preferable that they are thesame thickness for better uniformity of the thickness of the overalllayered product.

The ratio T1/T2 or T3/T4 of the thickness T1 (see FIG. 22) or T3 (seeFIG. 25) of the dielectric layer to the thickness T2 (see FIG. 22) or T4(see FIG. 25) of the metal thin film layer of each deposition unit ispreferably 20 or less, more preferably 15 or less. The ratio in thisrange improves the property of self-healing when opposing metal thinfilm layers are electrically shorted by, for example, a pin-hole in adielectric layer. The self-healing eradicates defects by burning orleaching of the metal thin film layer due to the overcurrent.

The surface roughness Ra (ten point average roughness) of the dielectriclayer is preferably not more than 0.1 μm, more preferably not more than0.02 μm. The surface roughness Ra (ten point average roughness) of themetal thin film layer is preferably not more than 0.1 μm, morepreferably not more than 0.02 μm. If the surface roughness is larger,electric field concentrations occur in small protrusions on the surface,and the dielectric layer may be damaged or the metal thin film layer maybe burnt. In a conventional film capacitor, external particles (forexample, inorganic particles such as silica or organic particles) aremixed in a film to provide a certain level of surface roughness for thepurpose of providing a conveyance property of the film and preventingblocking between films. As long as the present invention adopts thefollowing production method, it is not necessary to mix the externalparticles for the above reason for the layered product of the presentinvention, so that a layered product having good electriccharacteristics can be obtained. The surface roughness Ra (ten pointaverage roughness) of the present invention is measured with acontact-type surface meter having a diamond needle of 10 μm tip diameterand a 10 mg measuring load.

The curing degree of the dielectric layer is preferably 50-95%, morepreferably 70-90%. The curing degree means the extent of polymerizationand/or cross-linking when the resin is used as the dielectric layer. Ifthe curing degree is below these ranges, the layered product easily canbe deformed by external pressure, which occurs for example in the stepof pressing in the production process of the layered product or mountingthe layered product. This also can lead, for example to ruptures orshort-circuits of the metal thin film layer. On the other hand, if thecuring degree is above the above ranges, the following problems mayarise: Sprayed metal particles hardly penetrate between the metal thinfilm layers so that the adhesion strength of the external electrodes maybe reduced; or the layered product may break, for example when thecylindrical continuous layered product is removed from the can roller inthe production process of the layered layer as described later, orpressed into a flat layered base element or when external pressure isapplied in the step of mounting the layered product. To determine thecuring degree of the present invention, the ratio of the absorbance ofthe C═O groups and the C═C groups (1600 cm⁻¹) is determined with aninfrared spectrophotometer, the ratio of each monomer and the curedproduct is determined, and the curing degree is defined as 1 minus thereduced absorption ratio.

There is no limitation regarding the material of the dielectric layer aslong as it can be deposited to a thickness of 1 μm or less and canfunction as a dielectric satisfactorily, but a material comprising anacrylate resin or a vinyl resin as its main component is preferable.More specifically, a polymer of a polyfunctional (meth) acrylate monomeror polyfunctional vinyl ether monomer is preferable. Of these, forexample, a polymer of a dicyclopentadiene dimethanoldiacrylate orcyclohexane dimethanoldivinylether monomer or a polymer of a monomerwith substituted hydrocarbon groups is preferable because of theirelectric properties.

As the material of the metal thin film layer, at least one selected fromthe group consisting of Al, Cu, Zn, Sn, Au, Ag, and Pt is preferable. Ofthese, Al is preferable because of its deposition property andcost-efficiency. In some cases, it is preferable to oxidize the surfacefor the purpose of improving the resistance of the metal thin film layeragainst humidity. In addition to the metals described above, a smallamount of other elements or additives can be contained.

(Reinforcement Layer)

The reinforcement layers 503 a and 503 b of the first layered product(FIG. 20) of the present invention and the reinforcement layers 507 aand 507 b of the second layered product (FIG. 21) of the presentinvention are required to have either one of the structures C and Ddescribed below.

C: Comprising a deposition unit comprising a resin layer, a first metallayer and a second metal layer that are deposited on one surface of theresin layer and separated by a belt-shaped electrically insulating band.

D: Comprising a deposition unit comprising a resin layer and a metallayer that is deposited on one surface of the resin layer and in aportion except a belt-shaped electrically insulating band on one end ofthe surface of the resin layer.

Such a reinforcement layer is effective to prevent the element layerportion from being damaged by thermal load or external pressure in theprocess of manufacturing the layered product, or in the productionprocess of en electronic component using the same, especially acapacitor, or in the process of mounting the same on a printed circuitboard. Moreover, the reinforcement layer that has a metal thin filmlayer is effective to increase the adhesion strength of the externalelectrodes (see FIG. 33). That is to say, the adhesion strength of theexternal electrodes is mainly affected by the strength of the connectionwith the metal layer, whereas the strength of the connection with theresin layer contributes only little to the adhesion strength.Consequently, by providing a reinforcement layer comprising a metallayer, the adhesion strength of the external electrode of the capacitorcan be significantly increased. In the case where the layered product isprovided with an external electrode and is used as a capacitor, thereinforcement layer can function as a capacitance generation portion ofthe capacitor, but the capacitor design can be simplified when it doesnot function as such.

In the reinforcement layer having either structure C or D, anelectrically insulating band is formed on the resin layer. Without theelectrically insulating band, the opposite external electrodes would beshort-circuited via such a metal layer when the external electrodes (seeFIG. 33) are provided facing both the sides of the layered product. Theelectrically insulating band has a belt shape having a constant width tofacilitate production.

In the layered product of the present invention, the reinforcement layeris provided on both sides of the element layer. It is preferable toprovide the reinforcement layer on both sides, because protection of anelement layer and the adhesion strength of the external electrodesimprove more significantly.

The reinforcement layer can be deposited in contact with the elementlayer or can have another layer therebetween.

The reinforcement layer having either structure C or D comprises onlyone deposition unit, but it is preferable to deposit a plurality ofdeposition units in order to exert the effects of the reinforcementlayer more significantly.

The thickness (overall thickness on one surface) of the reinforcementlayer is preferably 20 μm or more, more preferably 50 to 500 μm, andmost preferably 100 to 300 μm to exert the effect of the reinforcementlayer sufficiently.

FIG. 28 is a cross-sectional view taken in the thickness direction(deposition direction) schematically illustrating an example of areinforcement layer where a plurality of deposition units having thestructure C are deposited.

A reinforcement layer 550 comprises at least one deposition unit 555comprising a resin layer 551 and a first metal layer 552 and a secondmetal layer 553 that are deposited on one surface of the resin layer551. The first metal layer 552 and the second metal layer 553 areseparated by a belt-shaped electrically insulating band 554.

The position in which the electrically insulating band is provided isnot limited to a particular position, but it is preferable to provide itsubstantially in the central portion of the reinforcement layer, asshown in FIG. 28. When it is provided substantially in the same positionas the electrically insulating portion of the element layer, a largerecess may be generated on the upper surface of the layered product.Therefore, for example in mounting onto a printed circuit board with asolder, the handling properties are poor and the wettability of thesolder is adversely affected. In addition, when such a recess isgenerated, as the depth of the recess is larger, it is more difficult toapply a patterning material to the bottom of the recess as describedlater. Therefore, it is difficult to form a good electrically insulatingportion or electrically insulating band having a constant width.Moreover, the generation of the recess causes inclination of thedielectric layer and the metal thin film layer deposited on the recessat both sides of the electrically insulating portion, so that thethickness of the deposition becomes small. Therefore, a reduction of thewithstand voltage as a capacitor, a pin-hole in the dielectric layer andpoor conductivity of the metal thin film layers are likely to occur.

When two or more deposition units as described above are deposited forthe reinforcement layer, it is preferable that the deposition positionsof the electrically insulating bands are not the same position over thereinforcement layer (the overall reinforcement layer on one side of theelement layer). For example, as shown in FIG. 29, the depositionposition of the electrically insulating band of the adjacent depositionunit is displaced by d1. Subsequently, the position of the electricallyinsulating band of the adjacent deposition unit is displaced by d1 ineither direction in the width direction of the electrically insulatingbands in the same manner. Alternatively, the positions of theelectrically insulating bands of two (or more) consecutive depositionunits can be the same position, and the position of the electricallyinsulating band of the third (or more) deposition unit can be displacedin the width direction of the electrically insulating band. When thedeposition positions are substantially the same position, a recess maybe generated in the electrically insulating band on a surface of thelayered product. Therefore, when mounting the layered product onto aprinted circuit board with a solder, the handling properties may be poorand the wettability of the solder may be adversely affected. Inaddition, when such a recess is generated, as the depth of the recess islarger, it is more difficult to apply a patterning material to thebottom of the recess as described later. Therefore, it is difficult toform a good electrically insulating band or electrically insulatingportion having a constant width. Moreover, the generation of the recesscauses inclination of the dielectric layer and the metal thin film layerdeposited on the recess at both sides of the electrically insulatingportion of the element layer, so that the thickness of the depositionbecomes small. Therefore, a reduction of the withstand voltage as acapacitor, a pin-hole in the dielectric layer and poor conductivity ofthe metal thin film layers are likely to occur.

On the other hand, when the displacement amount d1 is too large, notonly is the effect of eliminating the recess on the upper surface of thelayered product insignificant, but also the above-described problemsoccur due to the generation of the recess on the surface of the layeredproduct when the deposition position of the electrically insulating bandmatches the deposition position of the electrically insulating portion.Moreover, when the first metal layer and the second metal layer ofadjacent deposition units overlap, the overlapped portion forms acapacitor, which may cause a problem in the design of the capacitance orthe like.

FIG. 30 is a cross-sectional view taken in the thickness direction(deposition direction) schematically illustrating an example of areinforcement layer comprising a plurality of deposition units havingthe structure D.

A reinforcement layer 570 of this example includes a plurality ofdeposition units 574 comprising a resin layer 571 and a metal layer 572deposited on one surface of the resin layer. A metal layer is notprovided in a belt-shaped electrically insulating band portion 573 onone end of a surface of the resin layer.

When two or more deposition units having the structure D of thereinforcement layer are deposited, it is preferable that the widths ofthe electrically insulating bands are not the same over thereinforcement layer (the overall reinforcement layer on one side of theelement layer). For example, as shown in FIG. 31, with respect to anelectrically insulating band 581, the width of an electricallyinsulating band 582 of an adjacent deposition unit is changed andfurther the width of an electrically insulating band 583 of an adjacentdeposition unit is changed. Subsequently, the widths of the electricallyinsulating bands are changed sequentially in the same manner.Alternatively, the widths of the electrically insulating bands of two(or more) consecutive deposition units can be the same, and the width ofthe electrically insulating band of the third (or more) deposition unitcan be changed.

When all the widths of the electrically insulating bands are the same,the number of deposited metal thin film layers is small in the endportion where the electrically insulating bands are formed so that thedeposition thickness in this portion is small relative to the overalllayered product. Thus, a significant recess may be generated on an uppersurface of the layered product. This recess may deteriorate the handlingproperties when mounting the layered product onto a printed circuitboard with a solder and may adversely affect the wettability of thesolder. In addition, when such a recess is generated, as the depth ofthe recess is larger, it is more difficult to apply a patterningmaterial to the bottom of the recess as described later. Therefore, itis difficult to form a good electrically insulating band or electricallyinsulating portion having a constant width. Moreover, the generation ofthe recess causes inclination of the dielectric layer and the metal thinfilm layer deposited on the recess at a side of the electricallyinsulating portion of the element layer, so that the thickness of thedeposition of the dielectric layer and the metal thin film layer becomessmall locally. When the thickness of the deposition of the dielectriclayer becomes small locally, the following problem arises. In the casewhere the layered product is used as a capacitor, the presence of thatportion reduces the withstand voltage of the capacitor and causes ashort-circuit due to a pin-hole in the dielectric layer. Moreover, whenthe thickness of the deposition of the metal thin film layer becomessmall locally, poor conductivity is likely to occur in that portion.

The reinforcement layer does not necessarily form a capacitor generationportion as a capacitor when external electrodes are formed, but can beadapted to form the capacitance generation portion.

FIG. 32 is a cross-sectional view taken in the thickness direction(deposition direction) schematically illustrating an example of thereinforcement layer provided with a function as a capacitance generationportion of the capacitor.

A reinforcement layer 590 comprises a plurality of deposition units 594,each of which comprises a resin layer 591 and a metal layer 592deposited on one surface of the resin layer. The metal layer 592 is notprovided in a belt-shaped insulating band 593 on one end of the onesurface of the resin layer. Furthermore, the electrically insulatingbands of adjacent deposition units are positioned on opposite sides.More specifically, as shown in FIG. 32, in the case where a depositionunit 594 a is deposited adjacent to the deposition unit 594, theelectrically insulating band 598 of the deposition unit 594 is providedon the right end of the resin layer 591, an electrically insulating band593 a of the deposition unit 594 a is provided on the left end of aresin thin film layer 591 a. In this manner, the deposition units aredeposited sequentially in such a manner that the positions of theelectrically insulating portions are located on the opposite sides.Thus, when external electrodes are formed on the side portions of thelayered product (see FIG. 33), the reinforcement layer can function as acapacitor generation portion.

In this case, it is preferable that the widths of the electricallyinsulating bands of every other deposition unit of the reinforcementlayer are not the same over the reinforcement layer. More specifically,as shown in FIG. 32, with respect to the electrically insulating band593 of the deposition unit 594, the width of an electrically insulatingband 593 b of the deposition unit 594 b, which is one unit apart fromthe deposition unit 594, is different from that of the electricallyinsulating band 593. Thereafter, in the same manner, the width of theelectrically insulating portion of the deposition unit that is one unitapart is changed sequentially. Alternatively, the width of theelectrically insulating portion is the same as that of the electricallyinsulating portion of the deposition unit that is one unit apart, andthe width of the electrically insulating portion of the deposition unitthree units apart can be changed. This embodiment can prevent a recessfrom being generated on the upper surface of the element layer, so thatthe above problems hardly occur.

In the case where the resin layer is adapted to function as a capacitorgeneration portion of the capacitor, the deposition structure in FIGS.22, 24 and 25 shown as the deposition structure of the element layer canbe used instead of the structure in FIG. 32.

The materials for the resin layer and the metal layer of thereinforcement layer are not limited to particular materials, regardlessof the structure C or D. However, the materials used for the dielectriclayer and the metal thin film layer are preferable for the resin layerand the metal layer, respectively, in view of production efficiency. Onthe other hand, in some cases, materials different from those for thedielectric layer and the metal thin film layer are preferable for thepurpose of adjusting the adhesion strength with external electrodes oradjusting the curing degree or the mechanical strength of the overalllayered product or the like.

The curing degree of the resin layer of the reinforcement layer ispreferably 50-95%, more preferably 70-90%. If the curing degree issmaller than these ranges, the layered product can be deformed easily,for example by an external pressure applied in a pressing step duringproduction of the layered product or in a process for mounting thelayered product. On the other hand, if the curing degree is larger thanthese ranges, sprayed metal particles hardly penetrate between the metallayers during formation of external electrodes so that the adhesionstrength of the external electrodes becomes weak. Other problems such ascracking may arise, for example in the case where a cylindricalcontinuous layered product is removed from a can roller in theproduction process of the layered product, which will be describedlater, in the case where a flat layered base element is obtained bypressing, or in the case where an external pressure is applied in aprocess for mounting the layered product.

The thickness of the resin layer T5 (FIG. 28) and T7 (FIG. 30) ispreferably 0.1 to 1 μm, and more preferably 0.1 to 0.6 μm. The thicknessof the metal layer T6 (FIG. 28) and T8 (FIG. 30) is preferably 100 to500 Å, and more preferably 200 to 400 Å. The film resistance ispreferably 1 to 10Ω/□, and more preferably 2 to 6Ω/□. In the case ofFIG. 28, the thickness of the first metal layer can be different fromthat of the second metal layer, but the same thickness is preferablebecause a uniform thickness of the overall layered product can beobtained.

(Protective Layer)

The first layered product (FIG. 20) of the present invention is providedfurther with protective layers 504 a and 504 b on both sides of thereinforcement layer described above.

The protective layer is intended to prevent the element layer portion502 from being damaged by thermal load or external pressure in theproduction process of the layered product, in the production process ofan electronic component using the same, especially a capacitor, or in aprocess of mounting the same onto a printed board. Furthermore, withrespect to improvement of the adhesion strength of the externalelectrodes, although the contribution level is smaller than that of themetal thin film layer or the metal layer, the protective layer providesa certain effect.

The protective layers 504 a and 504 b are required to be provided onboth sides of the reinforcement layers 503 a and 503 b to achievesufficient protection of the element layer portion 502. The protectivelayer can be in contact with the reinforcement layer or have anotherlayer therebetween.

The thickness of the protective layer is not limited-to a particularvalue and can be determined suitably depending on the environment towhich the layered product is exposed. However, in order to provide theabove-described effect sufficiently, the thickness is preferably 2 μm ormore, more preferably 2 to 100 μm, and most preferably 4 to 30 μm.

The material for the protective layer is not limited to a particularmaterial, but when the material used for the dielectric layer and/or theresin layer is used, the production efficiency can be improved. On theother hand, a material different from that used for the dielectric layerand/or the resin layer can be used to provide a specific function forthe protective layer. For example, epoxy ester such as2-hydroxy-3-phenoxypropyl acrylate is preferable for better adhesionbetween the protective layer and the reinforcement layer.

The curing degree of the protective layer is preferably 50-95%, morepreferably 70-90%. If the curing degree is smaller than these ranges,the layered product can be deformed easily, for example by an externalpressure applied in a pressing step during production of the layeredproduct or in a mounting process of the layered product. On the otherhand, if the curing degree is larger than these ranges, problems such ascracking may arise in the case where a cylindrical continuous layeredproduct is removed from a can roller in the production process of thelayered product, which will be described later, in the case where a flatlayered base element is obtained by pressing, or in the case where anexternal pressure is applied in a mounting step of the layered product.

The protective layer can be colored to a specific color. This allows animprovement in accuracy of pattern recognition when mounting the layeredproduct on a printed circuit board as an electronic component orfacilitates the identification of each product. For example, coloringcan be performed by mixing a colorant such as a pigment or coating theouter surface with a paint. Moreover, the protective layer can be madetransparent, if necessary.

The protective layer is not indispensable to the second layered product(FIG. 21) of the present invention. However, the second layered productis required to satisfy at least one of E and F described below.

E: The thickness of the dielectric layer is different from that of theresin layer.

F: The thickness of the metal thin film layer is different from that ofthe metal layer.

More specifically, the thickness T1 (FIG. 22) or T3 (FIG. 25) of thedielectric layer of the element layer is required to be different fromthe thickness T5 (FIG. 28) or T7 (FIG. 30) of the resin layer of thereinforcement layer. In particular, it is preferable that the thicknessT5 (FIG. 28) or T7 (FIG. 30) of the resin layer of the reinforcementlayer is larger than the thickness T1 (FIG. 22) or T3 (FIG. 25) of thedielectric layer of the element layer.

Furthermore, the thickness T2 (FIG. 22) or T4 (FIG. 25) of the metalthin film layer of the element layer is required to be different fromthe thickness T6 (FIG. 28) or T8 (FIG. 30) of the metal layer of thereinforcement layer. In particular, it is preferable that the thicknessT6 (FIG. 28) or T8 (FIG. 30) of the metal layer of the reinforcementlayer is larger than the thickness T2 (FIG. 22) or T4 (FIG. 25) of themetal thin film layer of the element layer.

As described above, the reinforcement layer is provided for the purposeof protecting the element layer and improving the adhesion strength ofthe external electrodes. The protective layer is provided mainly for thepurpose of protecting the element layer and with some expectation forthe effect of improving the adhesion strength of the externalelectrodes. Therefore, in the second layered product (FIG. 21) of thepresent invention that is not provided with the protective layer, thereinforcement layer is required to function as the protective layer aswell. Thus, it is useful to change the thickness of each layer of theelement layer portion and the reinforcement layer portion. Inparticular, making the thickness of the resin layer or the metal layerof the reinforcement layer larger than that of the dielectric layer orthe metal thin film layer of the element layer is effective forprotection of the element layer and improvement of the externalelectrodes. In other words, the larger the thickness of the resin layeror the metal layer of the reinforcement layer is, the more effectively abuffer function against external pressure or thermal stress is provided.Furthermore, the external electrodes are formed by metal spraying, andthe particles of the sprayed metal are relatively rough so that theparticles hardly penetrate between the metal thin film layers of theelement layer. However, the thickness of the dielectric layer cannot belarge to ensure the capacitance for a capacitor. Therefore, making thethickness of the resin layer of the reinforcement layer largefacilitates the penetration of the sprayed metal and improves theadhesion strength of the external electrodes easily. Furthermore, thelarger the area of the metal layer exposed to the side is, the largerthe contact area with the external electrodes is. Therefore, theadhesion strength of the external electrodes can be improved by makingthe thickness of the metal layer of the reinforcement layer large.

Therefore, also for the first layered product (FIG. 20) of the presentinvention that is provided with the protective layer, it is preferablethat the thickness T1 (FIG. 22) or T3 (FIG. 25) of the dielectric layerof the element layer is different from the thickness T5 (FIG. 28) or T7(FIG. 30) of the resin layer of the reinforcement layer. In particular,it is preferable that the thickness T5 (FIG. 28) or T7 (FIG. 30) of theresin layer of the reinforcement layer is larger than the thickness T1(FIG. 22) or T3 (FIG. 25) of the dielectric layer of the element layer.Furthermore, it is preferable that the thickness T2 (FIG. 22) or T4(FIG. 25) of the metal thin film layer of the element layer is differentfrom the thickness T6 (FIG. 28) or T8 (FIG. 30) of the metal layer ofthe reinforcement layer. In particular, it is preferable that thethickness T6 (FIG. 28) or T8 (FIG. 30) of the metal layer of thereinforcement layer is larger than the thickness T2 (FIG. 22) or T4(FIG. 25) of the metal thin film layer of the element layer in view ofthe protection of the element layer and the improvement of the adhesionstrength of the external electrodes.

In the first and second layered products (FIGS. 20 and 21) of thepresent invention, the element layer has either one of the structures Aand B and the reinforcement layer has either one of the structures C andD. Therefore, the deposition structure can be one of four combinationsand any combination can be used and determined suitably based on theintended application of the layered product or required characteristics.

For example, in the case where the adhesion strength of the externalstrength is particularly required, it is preferable to choose A as theelement layer and C as the reinforcement layer. This is because theadhesion strength of the external electrodes depends significantly onthe connection strength with the metal thin film layer or the metallayer, and the connection strength with the dielectric layer or theresin thin film layer does not significantly contribute to it.Therefore, selecting A and C that have a larger number of metal thinfilm layers and metal layers improves the adhesion strength of theexternal electrodes significantly.

In order to obtain large capacitance for a capacitor, it is preferableto choose B as the element layer, because this allows a larger area ofthe dielectric layer that provides a capacitance generation portion.

Furthermore, for convenience of production, in many cases, it ispreferable to choose C as the reinforcement layer when A is chosen asthe element layer, and to choose D as the reinforcement layer when B ischosen as the element layer.

(External Electrodes)

The layered products of the first and second layered products of thepresent invention can be used as an electronic component or the likeeasily by forming external electrodes on both sides thereof that areopposed to each other.

FIG. 33 is a schematic perspective view of an example where externalelectrodes are formed in the first layered product (FIG. 20) of thesecond invention. In the case where the element layer 502 has thestructure A, the first metal thin film layer and the second metal thinfilm layer are electrically connected to external electrodes 601 a and601 b, respectively. In the case where the element layer 2 has thestructure B, the metal thin film layers of adjacent deposition units areelectrically connected to external electrodes 601 a and 601 balternately. Similarly, in the case where the reinforcement layers 503 aand 503 b have the structure C, the first metal layer and the secondmetal layer are electrically connected to external electrodes 601 a and601 b, respectively. In the case where the reinforcement layers 503 aand 503 b have the structure D, the metal layers are electricallyconnected to either one of the external electrodes 601 a and 601 b inthe case of the deposition forms in FIGS. 30 and 31, and the metallayers of adjacent deposition units are electrically connected to theexternal electrodes 601 a and 601 b alternately in the case of thedeposition forms in FIG. 32.

Also in the case where the external electrodes are to be formed in thesecond layered product (FIG. 21) of the present invention, the metalthin film layer and the metal layer are electrically connected to bothexternal electrodes, as in the case of FIG. 33.

The external electrodes can be formed by metal spraying with brass orthe like. Furthermore, the external electrodes can be constituted of aplurality of layers. For example, an underlying layer that iselectrically connected to the metal thin film layer of the element layeris formed by metal spraying, and another layer can be provided thereonby metal spraying, plating, coating or the like. More specifically, ametal having good adhesion strength with the layered product can beselected to form the underlying layer, and a metal having goodadhesiveness with various metal or resin that is to be contacted(deposited) thereon can be selected to form the upper layer.

Furthermore, melt solder plating, melt tinning, electroless solderplating or the like can be performed for a soldering property at thetime of mounting. In this case, as an underlying layer, the followinglayer can be formed: a layer obtained by applying a conductive pastewhere copper powder or the like has been dispersed in a thermosettingphenol resin and heating for curing; or a layer obtained by spraying ametal such as an alloy comprising copper/phosphorus/silver.

Furthermore, a bump electrode can be provided in the external electrodeto facilitate the mounting onto a circuit board further. The bumpelectrode can be formed by selecting a material suitably from knownmaterials or shapes.

Furthermore, a necessary outer package can be provided depending on theapplication. For example, a coating about several tens of angstromsthick is provided using a surface treatment agent such as a silanecoupling agent for the purpose of improving the resistance againsthumidity of the layered product or protecting exposed metal thin filmlayers and/or metal layers. Alternatively, a layer obtained by applyinga photocurable or thermosetting resin to a thickness of about severalhundreds μm and curing the resin can be provided.

The thus obtained layered product of the present invention can be usedas a chip capacitor, a chip coil, a chip resistor, and a compositeelement including these, and used suitably as an electronic componentsuch as a capacitor. In particular, the layered product of the presentinvention can be a capacitor having high capacitance, although it issmall. Therefore, when it is used as a chip capacitor, the practicalvalue is high.

(Production Method)

Next, a method for producing the layered product of the presentinvention will be described.

FIG. 34 is a schematic view illustrating an example of a productionapparatus for producing the layered product of the present invention.

A metal evaporation source 704 is provided at a lower portion of a canroller 701, which rotates in the direction of the arrow in FIG. 34 withconstant angular velocity or constant circumferential velocity. A resinevaporation source 702 is provided downstream in the rotation directionof the can roller 701, and an apparatus 703 for applying patterningmaterial is provided upstream thereof.

In this example, an apparatus 707 for removing patterning material isprovided between the metal evaporation source 704 and the resinevaporation source 702, and an apparatus 708 for curing resin and anapparatus 709 for treating a resin surface are provided between theresin evaporation source 702 and the apparatus 703 for applyingpatterning material. However, these apparatuses can be provided, ifnecessary.

The apparatuses are installed inside a vacuum container 705, wherein avacuum is maintained with a vacuum pump 706.

The circumferential surface of the can roller 701 is smooth, preferablymirror-finished, and cooled preferably to −20° C. to 40° C., morepreferably −10° C. to 10° C. The rotation velocity can be adjustedfreely, but preferably about 15 to 70 rpm.

The metal evaporation source 704 allows metal evaporation toward thesurface of the can roller 701 to form the metal thin film layer of theelement layer and the metal layer of the reinforcement layer. As theevaporation metal, for example, at least one selected from the groupconsisting of Al, Cu, Zn, Sn, Au, Ag, and Pt can be used. Instead ofevaporation, the metal thin film can be formed by a known technique suchas sputtering, ion plating or the like.

The resin evaporation source 702 allows a reactive monomer resin toevaporate and vaporize toward the surface of the can roller 701. Theresin is deposited so as to form the dielectric layer of the elementlayer, the resin layer of the reinforcement layer and the protectivelayer.

If necessary, the deposited reactive monomer resin can be polymerizedand/or cross-linked with the apparatus 708 for curing resin and cured toa predetermined curing degree. As the apparatus for curing resin, anelectron beam irradiation device or a UV beam irradiation device can beused, for example.

If necessary, the surface of the formed resin thin film is treated withthe apparatus 709 for treating a resin surface. For example, the surfaceof the resin layer can be activated with an oxygen plasma to increasethe adhesiveness with the metal thin film.

The apparatus 703 for applying patterning material deposits a patterningmaterial on the surface of the resin thin film in a belt-shape. At theportions where the patterning material has been deposited, no metal thinfilm is formed, so that these portions become the electricallyinsulating portions of the element layer and the electrically insulatingbands of the reinforcement layer. As the patterning material, forexample, oil can be used. To apply the patterning material, evaporatedand vaporized patterning material can be ejected from a nozzle andcondensed on the surface of the resin thin film, or liquid patterningmaterial can be ejected. Besides these examples of contactlessapplication methods, other application methods such as reverse coatingor die coating are possible, but for the present invention, contactlessapplication methods are preferable because no external pressure isapplied to the resin surface. Especially, a method of condensing theevaporated patterning material on the surface of the resin thin film ispreferable because the structure is relatively simple.

FIG. 35 is a schematic perspective view of an apparatus for applyingpatterning material that applies a belt-shaped oil film on a surface ofa resin thin film by ejecting evaporated oil as an example of theapparatus for applying patterning material. The apparatus is provided insuch a manner that a plane 711 of the apparatus 703 for applyingpatterning material is perpendicular to the normal line of thecircumferential surface of the can roller 701. On the plane 711, apredetermined number of nozzles 712 for ejecting vaporized oil arearranged at predetermined intervals. The shape of the nozzle 712 can beround, as shown in FIG. 35, but elliptical, elongated, rectangular orother shapes are also possible. Alternatively, a plurality ofelliptical, elongated or rectangular nozzles can be arranged in thetravel direction of the surface of the can roller.

The patterning material applied with the apparatus 703 for applyingpatterning material can be removed by an apparatus 707 for removingpatterning material, if necessary. There is no particular limitationregarding how the patterning material is removed. However, for example,when oil is used as the patterning material, the patterning material canbe removed by heat evaporation by a heater, or decomposition by plasmairradiation, or a combination thereof. In this case, oxygen plasma,argon plasma, nitrogen plasma, or the like can be used for the plasmairradiation, but among these, oxygen plasma is most preferable.

In the layered product of the present invention, rotating the can roller701 forms the protective layer, the reinforcement layer, the elementlayer, the reinforcement layer and the protective layer on thecircumferential surface thereof in this order.

In order to form the element layer as shown in FIGS. 22, 24, 25 and 27,it is required to move the deposition position of the patterningmaterial by a predetermined distance in the direction perpendicular tothe travel direction of the circumferential surface of the can roller701 for the purpose of changing the position of the electricallyinsulating portion, every time one deposition unit comprising thedielectric layer and the metal thin film layer is deposited. Similarly,in order to form the reinforcement layer as shown in FIGS. 29, 31 and32, it is required to move the deposition position of the patterningmaterial by a predetermined distance in the direction perpendicular tothe travel direction of the circumferential surface of the can roller701 for the purpose of changing the position of the electricallyinsulating band, every time one deposition unit comprising the resinlayer and the metal layer is deposited.

Furthermore, in the process of producing the layered product, since thedeposition thickness becomes larger as the deposition units aredeposited sequentially, it is preferable to retract the apparatus 703for applying patterning material as the deposition progresses, not onlyin the case where the patterning material is directly applied by coatingor the like, but also in the case where deposition is performed by acontactless method. In other words, in FIG. 34, it is preferable todeposit layers while constantly maintaining a distance Dn between thecircumferential surface of the layered product that is being formed onthe can roller 701 and the end of the nozzles of the apparatus forapplying patterning material at a predetermined interval. This isbecause the patterning material diffuses with a certain directivityespecially when vaporized oil is ejected for deposition, so that avariation of the distance Dn changes the deposition width, whereby theelectrically insulating portion having a predetermined width cannot beobtained stably.

The retraction of the apparatus for applying patterning material and themovement of the deposition position of the patterning material can beperformed, for example by an apparatus as shown in FIG. 36.

First, the apparatus for applying patterning material is retracted inthe following manner. An actuator A 802 is fixed on a movable base 801.The apparatus 703 for applying patterning material is attached to themobile end of the actuator A 802. The actuator A 802 can move theapparatus 703 for applying patterning material in the direction of arrow803 on the movable base 801. A gap measuring device 804 for measuringthe distance to the surface of the can roller 701 (the circumferentialsurface of the layered product in the process of the formation of thelayered product) is provided on the apparatus 703 for applyingpatterning material. A contactless measuring device, for example ameasuring device using a laser, can be used for the gap measuring device804. During the manufacturing of the layered product, the gap measuringdevice 804 keeps measuring the distance to the circumferential surfaceof the layered product on the surface of the can roller 701, and asignal corresponding to this measurement is sent to a gap measuringcircuit 805. The gap measuring circuit 805 continuously checks whetherthe distance between the nozzle end of the apparatus 703 for applyingpatterning material and the surface of the can roller 701 (thecircumferential surface of the layered product during the formation oflayers) is within a predetermined range. When the deposition progressesand the gap measuring circuit 805 determines that this distance issmaller than the predetermined range, it instructs the actuator A 802 toretract the apparatus 703 for applying patterning material apredetermined distance, and based on this instruction, the apparatus 703for applying patterning material is retracted a predetermined distance.Thus, the distance Dn between the nozzle end of the apparatus 703 forapplying patterning material and the circumferential surface of thelayered product on the can roller 701 always can be kept within aconstant interval while the deposition progresses.

As an alternative to the control using the gap measuring device 804 andthe gap measuring circuit 805 as described above, the apparatus forapplying patterning material also can be retracted for a preset lengthbased on the layering thickness, in accordance with the number ofrotations of the can roller 701. Moreover, the distance measurement withthe gap measuring device 804 described above can be used in thisconfiguration for verification.

Next, the position where the patterning material is applied can bechanged in the following manner. An actuator B 807 is attached to asupport base 806. The movable base 801 is attached to the mobile end ofthe actuator B 807. The actuator B 807 can move the movable base 801 onthe support base 806 in the direction indicated by arrow 808. Therotation of the can roller 701 is observed by a rotation detector (notshown in the drawing), which sends a rotation signal S1 to a rotationdetecting circuit 809 whenever the can roller 701 has rotated one turn.When the rotation detecting circuit 809 has counted a predeterminednumber of detections of the rotation signal S1 (for example onedetection), it instructs the actuator B 807 to move the movable base 801for a predetermined distance in a predetermined direction as indicatedby arrow 808. Thereby, the movable base 801, and thus the apparatus 703for applying patterning material, is moved a predetermined distance in apredetermined direction as indicated by arrow 808. Thus, the positionwhere patterning material is applied can be changed for everypredetermined number of rotations of the can roller 701 for apredetermined distance in a direction that is perpendicular to therotation and travel direction of the surface of the can roller 701.

In this manner, the reinforcement layer and the element layer are formedon the circumferential surface of the can roller 701. The reinforcementlayer comprises a plurality of deposition units, each of which comprisesthe resin layer and the metal layer deposited in a portion except thebelt-shaped electrically insulating band, and the element layercomprises a plurality of deposition units, each of which comprises thedielectric layer and the metal thin film layer deposited in a portionexcept the belt-shaped electrically insulating portion. In order to formthe protective layer, before and after the formation of thereinforcement layer, only resin can be deposited with the resinevaporation source 702 by rotating the can roller 701 until apredetermined thickness is formed while providing shielding plates orthe like to prevent the metal evaporation source 704 and the apparatus703 for applying patterning material from functioning.

Thus, a cylindrical continuous product of the layered product of thepresent invention is formed on the circumferential surface of the canroller 701. This is divided in the radial direction (e.g., into 8sections by every 45°) and removed from the can roller 701. The sectionsare pressed under heat and pressure, and flat layered base elements areobtained.

FIG. 37 is a partial perspective view illustrating an example of theoutline of the structure of the flat layered base element obtained inthe above-described manner. In FIG. 37, arrow 901 indicates the traveldirection (circumferential direction) on the can roller 701.

The layered base element 900 in FIG. 37 includes a protective layer 904b, a reinforcement layer 903 b, an element layer 902, a reinforcementlayer 903 a and a protective layer 904 a, which are deposited on the canroller 701 in this order.

Thereafter, the layered base element is cut along cutting planes 905 aand 905 b so that the layered product of the present invention isobtained. In this example, the first layered product (FIG. 20) where theelement layer has the structure in FIG. 22 and the reinforcement layerhas the structure in FIG. 28 can be obtained.

A layered product comprising various kinds of element layers orreinforcement layers can be obtained by suitably changing the positionon which patterning material is applied and the positions of the cuttingplanes 905 a.

The method described above can provide the layered product of thepresent invention efficiently and inexpensively in a simple method.

Hereinafter, the second invention will be described by way of examplesmore specifically.

EXAMPLE 6

The first layered product of the present invention as shown in FIG. 20comprising “a protective layer/a reinforcement layer/an element layer/areinforcement layer/a protective layer” was produced.

The production method thereof is as follows.

The layered product was produced using the apparatus shown in FIG. 34. Avacuum container 705 was evacuated to 2×10⁻⁴ Torr, and thecircumferential surface of the can roller 701 was maintained at 5° C.

First, a portion that is to serve as a protective layer was deposited onthe circumferential surface of the can roller 701. Dicyclopentadienedimethanol diacrylate was used as the material of the protective layer,and evaporated so as to be deposited on the circumferential surface ofthe can roller 701 with the resin evaporation source 702. Then, a UVcuring device was used as the apparatus 708 for curing resin topolymerize and cure the protective layer material deposited in theabove-described manner. This operation was repeated by rotating the canroller 701 so that the protective layer having a thickness of 15 μm wasformed on the circumferential surface of the can roller 701.

Then, a portion that is to serve as a reinforcement layer was deposited.The same material as that for the protective layer was used as the resinlayer material, and evaporated so as to be deposited on the protectivelayer with the resin evaporation source 702. Then, a UV curing devicewas used as the apparatus 708 for curing resin to polymerize and curethe resin layer material deposited in the above-described manner. Thethickness of the thus formed resin layer was 0.4 μm. Thereafter, thesurface was treated with oxygen plasma with the apparatus 709 fortreating resin surface. Next, a pattering material was applied in aportion corresponding to the electrically insulating band with theapparatus 703 for applying pattering material. A fluorocarbon oil wasused as the pattering material, and evaporated and ejected from a nozzlehaving a diameter of 50 μm so as to be deposited in the form of a belthaving a width of 150 μm. Then, aluminum was deposited with the metalevaporation source 704. The deposition thickness was 300 Å, and the filmresistance was 3Ω/□. Thereafter, the residual patterning material wasremoved by heating with a far infrared radiation heater and a plasmadischarge treatment using the apparatus 707 for removing patterningmaterial. This operation was repeated 500 times by rotating the canroller 701 so that the reinforcement layer having a total thickness of215 μm was formed. The movement of the apparatus for applying patterningmaterial in the direction perpendicular to the travel direction of thecircumferential surface of the can roller 701 (the direction indicatedby arrow 808 in FIG. 36) was performed with the device shown in FIG. 36in the following pattern. When the can roller 701 had rotated one turn,the apparatus moved 60 μm in a first direction. Then, the apparatus wasshifted 60 μm in the same first direction after the next rotation; itwas shifted 60 μm in a second direction opposite to the first directionafter the next rotation; and then it was shifted 60 μm in the samesecond direction after the next rotation. These shifts constituted onecycle, which was repeated thereafter. The distance Dn between the nozzle712 of the apparatus for applying patterning material and the adherencesurface was controlled to be maintained constantly at 250 to 300 μm.Thus, the reinforcement layer portion as shown in FIG. 29 was obtained.

Next, the element layer portion comprising dielectric layers and metalthin film layers was deposited. The same material as that for theprotective layer and the resin layer was used as the dielectric layermaterial, and evaporated so as to be deposited on the reinforcementlayer. Then, a UV curing device was used as the apparatus 708 for curingresin to polymerize and cure the dielectric layer material deposited inthe above-described manner. The thickness of the thus formed dielectriclayer was 0.4 μm. Thereafter, the surface was treated with oxygen plasmawith the apparatus 709 for treating resin surface. Next, a patteringmaterial was applied in a portion corresponding to the electricallyinsulating portion with the apparatus 703 for applying patteringmaterial. A fluorocarbon oil was used as the pattering material, andevaporated and ejected from a nozzle having a diameter of 50 μm so as tobe deposited in the form of a belt having a width of 150 μm. Then,aluminum was deposited with the metal evaporation source 704. Thedeposition thickness was 300 Å, and the film resistance was 3Ω/□.Thereafter, the residual patterning material was removed by heating witha far infrared radiation heater and a plasma discharge treatment usingthe apparatus 707 for removing patterning material. This operation wasrepeated 2000 times by rotating the can roller 701 so that the layeredproduct portion having a total thickness of 860 μm was formed. Themovement of the apparatus for applying patterning material in thedirection perpendicular to the travel direction of the circumferentialsurface of the can roller 701 (the direction indicated by arrow 808 inFIG. 36) was performed with the device shown in FIG. 36 in the followingpattern. When the can roller 701 had rotated one turn, the apparatus wasshifted 1000 μm in a first direction; and after the next rotation, theapparatus was shifted 940 μm in a second direction opposite to the firstdirection; after the next rotation, it was shifted 1000 μm in the firstdirection; after the next rotation, it was shifted 940 μm in the seconddirection; after the next rotation, it was shifted 1000 μm in the firstdirection; after the next rotation, it was shifted 1060 μm in the seconddirection; after the next rotation, it was shifted 1000 μm in the firstdirection; and after the next rotation, it was shifted 1060 μm in thesecond direction. These shifts constituted one cycle, which was repeatedthereafter. The distance Dn between the nozzles 712 of the apparatus forapplying patterning material and the adherence surface was controlled tobe maintained constantly at 250 to 300 μm. Thus, the element layerportion as shown in FIG. 24 was obtained.

Next, a reinforcement layer portion having a thickness of 215 μm wasformed on a surface of the element layer portion. The method thereof wasexactly the same as the method for the reinforcement layer as describedabove.

Finally, a protective layer portion having a thickness of 15 μm wasformed on a surface of the reinforcement layer. The method thereof wasexactly the same as the method for the protective layer as describedabove.

Then, the obtained cylindrical layered product was cut into 8 sectionsin the radial direction (separated by 45°) and removed. The sectionswere pressed under heat, and flat layered base elements as shown in FIG.37 were obtained (however, in reality, the deposition positions of theelectrically insulating portions of the element layer portion and theelectrically insulating band of the reinforcement layer portion areslightly displaced, as shown in FIGS. 24 and 29). The flat layered baseelements were cut along the cutting planes 905 a, and the cutting planeswere metallized with brass so as to form external electrodes. Anelectrically conducting paste where copper powder had been dispersed ina thermosetting phenol resin was applied to the metallized surface,heat-cured, and the resulting resin surface was plated with moltensolder. After that, the pieces were cut along the cutting planes 905 bin FIG. 37, and immersed in a silane coupling agent to coat thecircumferential surface, whereby chip capacitors were obtained.

The width of the electrically insulating portion of the element layerwas 150 μm, and the displacement amount d in the deposition position ofthe electrically insulating portion of every other deposition unit was60 μm. The width of the electrically insulating band of thereinforcement layer was 150 μm and was positioned substantially in thecenter in the width direction, and the displacement amount d1 betweenthe deposition positions of the electrically insulating bands ofadjacent deposition units was 60 μm.

The obtained chip capacitor had a thickness in the deposition directionof 1.3 mm, a depth of 1.6 mm and a width (in the direction between theopposite external electrodes) of 3.2 mm, which was small, and yet thecapacitance was 0.47 μF. The withstand voltage was 50V. Furthermore,roughness was not substantially observed on the upper and lower surfacesin the deposition direction. This was mounted onto a printed circuitboard with a solder. There was no problems such as the externalelectrodes falling off. When the obtained chip capacitor was dismantled,and the surface roughnesses Ra of the surface of the dielectric layerand the surface of the metal thin film layer were measured, the resultswere 0.005 μm and 0.005 μm, respectively. The curing degrees of thedielectric layer, the resin layer and the protective layer were 95%, 95%and 90%, respectively.

EXAMPLE 7

The first layered product of the present invention as shown in FIG. 20comprising “a protective layer/a reinforcement layer/an element layer/areinforcement layer/a protective layer” was produced in the same mannerin Example 6.

However, the deposition conditions of the patterning material of thereinforcement layer and the element layer were changed as follows.

The diameter of the nozzle of the apparatus for applying patterningmaterial was changed to 75 μm, and the patterning material was depositedin a belt shape having a width of 200 μm. The movement of the apparatusfor applying patterning material in the direction perpendicular to thetravel direction of the circumferential surface of the can roller 701(the direction indicated by arrow 808 in FIG. 36) was performed with thedevice shown in FIG. 36 in the following pattern.

For the reinforcement layer portion, the apparatus was shifted 60 μm ina first direction after one rotation of the can roller 701; after thenext rotation, it was shifted 60 μm in the same first direction; afterthe next rotation, it was shifted 60 μm in a second direction oppositeto the first direction; and after the next rotation, it was shifted 60μm in the same second direction. These shifts constituted one cycle,which was repeated thereafter. Thus, the reinforcement layer portion asshown in FIG. 31 was obtained.

For the element layer portion, the apparatus was shifted 1000 μm in afirst direction after one rotation of the can roller 701; after the nextrotation, it was shifted 940 μm in a second direction opposite to thefirst direction; after the next rotation, it was shifted 1000 μm in thefirst direction; after the next rotation, it was shifted 940 μm in thesecond direction; after the next rotation, it was shifted 1000 μm in thefirst direction; after the next rotation, it was shifted 1060 μm in thesecond direction; after the next rotation, it was shifted 1000 μm in thefirst direction; and after the next rotation, it was shifted 1060 μm inthe second direction. These shifts constituted one cycle, which wasrepeated thereafter. Thus, the element layer portion as shown in FIG. 27was obtained.

Thereafter, flat layered base elements 900′ as shown in FIG. 38 wereobtained in the same manner as in Example 6. The direction of arrow 901′indicates the travel direction (circumferential direction) on the canroller 701. In the obtained layered base element, a protective layer 904b′, a reinforcement layer 903 b′, an element layer 902′, a reinforcementlayer 903 a′, and a protective layer 904 a′ are deposited in this order(however, in reality, the deposition positions of the electricallyinsulating portions of the element layer portion and the electricallyinsulating band of the reinforcement layer portion are slightlydisplaced, as shown in FIGS. 27 and 31). The flat layered base elementswere cut along the cutting planes 905 a′, and the cutting planes weremetallized with brass so as to form external electrodes. An electricallyconducting paste where copper powder had been dispersed in athermosetting phenol resin was applied to the metallized surface,heat-cured, and the resulting resin surface was plated with moltensolder. After that, the pieces were cut along the cutting planes 906 b′in FIG. 38, and immersed in a silane coupling agent to coat thecircumferential surface, whereby chip capacitors were obtained.

The average width of the electrically insulating portion of the elementlayer was 140 μm, and the largest width thereof was 200 μm and thesmallest width was 80 μm.

The obtained chip capacitor had a thickness in the deposition directionof 1.5 mm, a depth of 1.6 mm and a width (in the direction between theopposite external electrodes) of 3.2 mm, which was small, and yet thecapacitance was 0.47 μF. The withstand voltage was 50V. Furthermore,roughness was not substantially observed on the upper and lower surfacesin the deposition direction. This was mounted onto a printed circuitboard with a solder. There was no problems such as the externalelectrodes falling off. Although the number of the metal thin filmlayers and the metal layers that are connected to the externalelectrodes is significantly smaller than that of Example 6, sufficientadhesion strength was obtained. This is believed to be because theinterval between the metal thin film layers of the element layer is wideso that the sprayed metal particles can penetrate sufficiently betweenthe metal thin film layers. When the obtained chip capacitor wasdismantled, and the surface roughnesses Ra of the surface of thedielectric layer and the surface of the metal thin film layer weremeasured, the results were 0.005 μm and 0.005 μm, respectively. Thecuring degrees of the dielectric layer, the resin layer and theprotective layer were 95%, 95% and 90%, respectively.

COMPARATIVE EXAMPLE 2

A chip capacitor using the layered product as shown in FIG. 21 wasobtained in the same manner as in Example 6 except that the protectivelayer was not formed.

The obtained chip capacitor had a thickness in the deposition directionof 0.97 mm (this is thinner than in Example 6, because the protectivelayer was not formed), a depth of 1.6 mm and a width (in the directionbetween the opposite external electrodes) of 3.2 mm, which was small,and yet the capacitance was 0.40 μF. The withstand voltage was 35V. Noneof them were better than those in Example 6. This is believed to bebecause the layered product was damaged by thermal load or externalpressure in the production process of the layered product. Roughness wasnot substantially observed on the upper and lower surfaces in thedeposition direction. When this was mounted onto a printed circuit boardwith a solder, the external electrodes were missing in some chipcapacitors. When the obtained chip capacitor was dismantled, and thesurface roughnesses Ra of the surface of the dielectric layer and thesurface of the metal thin film layer were measured, the results were0.005 μm and 0.005 μm, respectively. The curing degrees of thedielectric layer and the resin layer were 95% and 95%, respectively.

EXAMPLE 8

A chip capacitor using the second layered product of the presentinvention (FIG. 21) was obtained in the same manner as in ComparativeExample 2 except that the thicknesses of the resin layer and the metallayer of the reinforcement layer were made larger by adjusting therotational speed of the can roller. The thickness of the resin layer ofthe reinforcement layer was 0.6 μm, the deposition thickness of themetal layer was 500 Å, and the film resistance was 2Ω/□. The number ofdepositions was the same as that of Comparative Example 2.

The obtained chip capacitor had a thickness in the deposition directionof 1.8 mm (this is thicker than in Comparative Example 2, because thethickness of each layer of the reinforcement layer is larger), a depthof 1.6 mm and a width (in the direction between the opposite externalelectrodes) of 3.2 mm, which was small, and yet the capacitance was 0.47μF. The withstand voltage was 50V. All of them were better than those inComparative Example 2. This is believed to be because the bufferfunction of the reinforcement layer served sufficiently against thermalload or external pressure in the production process of the layeredproduct. Roughness was not substantially observed on the upper and lowersurfaces in the deposition direction. When this was mounted onto aprinted circuit board with a solder, external electrodes falling off orthe like was not observed. The reason why the chip capacitor in thisexample is better than that in Comparative Example 2 is believed to beas follows. A larger thickness of the resin layer of the reinforcementlayer facilitates the penetration by the sprayed metal particles of theexternal electrodes. In addition, a larger thickness of the metal layerenlarges the area of metal layer exposed to the sides so that thecontact area with the external electrodes become large. When theobtained chip capacitor was dismantled, and the surface roughnesses Raof the surface of the dielectric layer and the surface of the metal thinfilm layer were measured, the results were 0.005 μm and 0.005 μm,respectively. The curing degrees of the dielectric layer and the resinlayer were 95% and 95%, respectively.

The embodiments and the examples disclosed in this application areintended to describe the technical idea of the first and secondinvention and are to be considered as illustrative and not limiting thepresent first and second inventions. The present invention may beembodied in other forms without departing from the spirit or essentialcharacteristics thereof and the scope of the invention, and all changeswhich come within the meaning and range of equivalency of the claims areintended to be embraced therein.

INDUSTRIAL APPLICABILITY

Regarding the First Invention

The layered product of the first present invention has good surfaceproperties even if the deposition thickness is small and contains noforeign substance therein. Therefore, the requirements for a highperformance thin layered product can be satisfied. Thus, the firstpresent invention can be used in a wide range of applications thatrequire high levels of these requirements, such as a magnetic recordingmedium such as a magnetic tape, a wrapping material, and an electroniccomponent. In particular, when the present invention can be usedsuitably as a capacitor, especially as a chip capacitor, compact andhigh capacitance capacitors having stable qualities can be obtained atlow cost. In addition, when the present invention is used to produce achip coil, a noise filter, a chip resistor or other electroniccomponents, the compactness and high performance of these electroniccomponents can be achieved.

Regarding the Second Invention

The layered product of the second present invention has strongresistance against thermal load and external pressure, and therefore canbe used in a wide range of applications that requires high levels ofthese requirements, such as a magnetic recording medium such as amagnetic tape, a wrapping material, and an electronic component. Inparticular, since the layered product of the second present inventionhas high adhesion strength when external electrodes are formed, it canbe used suitably as an electronic component. For example, when it isused as a capacitor, especially as a chip capacitor, compact and highcapacitance capacitors having good quality can be obtained. In addition,when the present invention is used to produce a chip coil, a noisefilter, a chip resistor or other electronic components, the compactnessand high performance of these electronic components can be achieved.

What is claimed is:
 1. A layered product comprising an element layer,reinforcement layers deposited on both sides of the element layer, andprotective layers deposited further on both sides of the reinforcementlayers, wherein the element layer comprises a plurality of depositionunits, each deposition unit comprising a dielectric layer, and a metalthin film layer that is deposited on one surface of the dielectriclayer, the metal thin film layer being absent from a belt-shapedelectrically insulating portion at one end of the surface of thedielectric layer, and is deposited in such a manner that theelectrically insulating portions of adjacent deposition units arepositioned on opposite sides; and the reinforcement layers comprise adeposition unit that comprises a resin layer, and a metal layer that isdeposited on one surface of the resin layer, the metal layer beingabsent from a belt-shaped electrically insulating portion on one end ofthe surface of the resin layer.
 2. The layered product according toclaim 1, wherein a thickness of the metal thin film layer is differentfrom that of the metal layer.
 3. The layered product according to claim1, wherein a thickness of the dielectric layer is different from that ofthe resin layer.
 4. The layered product according to claim 1, wherein athickness of at least one of the protective layers is not less than 2μm.
 5. The layered product according to claim 1, wherein a material ofthe protective layer is different from a material of the dielectriclayer.
 6. The layered product according to claim 1, wherein a curingdegree of the protective layer is 50 to 95%.
 7. A layered productcomprising an element layer and reinforcement layers deposited on bothsides of the element layer, wherein the element layer comprises aplurality of deposition units, each deposition unit comprising adielectric layer, and a metal thin film layer that is deposited on onesurface of the dielectric layer, the metal thin film layer being absentfrom a belt-shaped electrically insulating portion on one end of thesurface of the dielectric layer, and is deposited in such a manner thatthe electrically insulating portions of adjacent deposition units arepositioned on opposite sides; the reinforcement layers comprise adeposition unit that comprises a resin layer, and a metal layer that isdeposited on one surface of the resin layer, the metal layer beingabsent from a belt-shaped electrically insulating portion on one end ofthe surface of the resin layer; and at least one of the followingconditions is satisfied: a thickness of the dielectric layer isdifferent from a thickness of the resin layer; a thickness of the metalthin film layer is different from a thickness of the metal layer.
 8. Thelayered product according to claim 1 or 7, wherein a curing degree ofthe resin layer is 50 to 95%.
 9. The layered product according to claim1 or 7, wherein widths of electrically insulating portions of everyother deposition unit of the element layer are not the same over theelement layer.
 10. The layered product according to claim 1 or 7,wherein the element layer comprises at least 100 deposition units. 11.The layered product according to claim 1 or 7, wherein a thickness ofthe dielectric layer is not more than 1 μm.
 12. The layered productaccording to claim 1 or 7, wherein a thickness of the dielectric layeris not more than 0.7 μm.
 13. The layered product according to claim 1 or7, wherein a film resistance of the metal thin film layer is not lessthan 2Ω/□.
 14. The layered product according to claim 1 or 7, wherein (athickness of the dielectric layer)/(a thickness of the metal thin filmlayer)≦20.
 15. The layered product according to claim 1 or 7, wherein acuring degree of the dielectric layer is 50 to 95%.
 16. The layeredproduct according to claim 1 or 7, wherein the metal thin film layercomprises aluminum or an oxide thereof.
 17. The layered productaccording to claim 1 or 7, wherein the reinforcement layer comprises aplurality of deposition units.
 18. The layered product according toclaim 1 or 7, wherein a thickness of each of the reinforcement layers isnot less than 20 μm.
 19. The layered product according to claim 17,wherein widths of the electrically insulating bands are not the sameover the reinforcement layer.
 20. The layered product according to claim17, wherein electrically insulating bands of adjacent deposition unitsof the reinforcement layer are deposited so as to be positioned onopposite sides.
 21. The layered product according to claim 20, whereinwidths of electrically insulating bands of every other deposition unitof the reinforcement layer are not the same over the reinforcementlayer.
 22. The layered product according to claim 1 or 7, wherein amaterial of the resin layer is different from a material of thedielectric layer.
 23. The layered product according to claim 1 or 7,wherein a thickness of the resin layer is larger than a thickness of thedielectric layer.
 24. The layered product according to claim 1 or 7,wherein a thickness of the metal layer is larger than a thickness of themetal thin film layer.
 25. The layered product according to claim 1 or7, further comprising external electrodes are formed on opposed sides ofthe layered product.
 26. The layered product according to claim 25,wherein the external electrodes comprise a plurality of layers.
 27. Thelayered product according to claim 26, wherein a layer of the externalelectrodes is electrically connected to the metal thin film layer, andis formed by metal spraying.
 28. The layered product according to claim25, wherein the external electrodes comprise a bump electrode.
 29. Thelayered product according to claim 1 or 7, further comprising an outerpackage on an outer surface.
 30. A capacitor produced using the layeredproduct according to claim 1 or
 7. 31. The capacitor according to claim30, wherein the capacitor is a chip capacitor.